Operation Manual
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1440 HIGH VOLTAGE
WARRANTY
LeCROY CORPORATION warrants each instrument it manufactures
to be free from defects in material and workmanship under normal use and
service for the period of 1 year from the date of purchase. Custom monolithics
and hybrids sold separately and all spare or replacement parts and repairs
are warranted for 90 days. This warranty extends only to the original purchaser
and shall not apply to fuses, disposable batteries, or any product of parts
which have been subject to misuse, neglect, accident or abnormal conditions
of operations.
In the event of failure of a product covered by this warranty, LeCroy
will repair and calibrate an instrument returned to the factory or an authorized
service facility within one year of the original purchase; provided the
warrantor's examination discloses to its satisfaction that the product
was defective. The warrantor may, at its option, replace the product in
lieu of repair. With regard to any instrument returned within one year
of the original purchase, said repairs or replacement will be made without
charge. If the failure has been caused by misuse, neglect, accident, or
abnormal conditions or operations, repairs will be billed at a nominal
cost. In such cases, an estimate will be submitted before work is started,
if requested.
The foregoing warranty is in lieu of all other warranties, express
or implied, including but not limited to any implied warranty of merchantability,
fitness, or adequacy for any particular purpose or use. LeCroy Corporation
shall not be liable for any special, incidental, or consequential damages,
whether in contract, tort or otherwise.
IF ANY FAILURE OCCURS, notify LeCroy Corporation or the nearest
service facility, giving full details of the difficulty, and include the
Model number, serial number, and FAN (Final Assembly Number) or ECO (Engineering
Change Order) number. On receipt of this information, service data or shipping
instructions, forward the instrument, transportation prepaid.
A Return Authorization Number will be given as part of shipping
instructions. Marking this RA number on the outside of the package will
insure that it goes directly to the proper department within LeCroy. Repairs
will be made at the service facility and the instrument returned transportation
prepaid.
ALL SHIPMENTS OF LECROY INSTRUMENTS FOR REPAIR OR ADJUSTMENT
should be made via Air Freight or "Best May" prepaid. The instrument should
be shipped in the original packing carton; or if it is not available, use
any suitable container that is rigid and of adequate size. If a substitute
container is used, the instrument should be wrapped in paper and surrounded
with at least four inches of excelsior or similar shock-absorbing material.
IN THE EVENT OF DAMAGE IN SHIPMENT to original purchaser
the instrument should be thoroughly inspected immediately upon original
delivery to purchaser. All material in the container should be checked
against the enclosed Packing List. The manufacturer will not be responsible
for shortages against the packing sheet unless notified promptly. If the
instrument is damaged in any way, a claim should be filed with the carrier
immediately. (To obtain a quotation to repair shipment damage, contact
the LeCroy factory or the nearest service facility).
DOCUMENTATION DISCREPANCIES OR OMISSIONS. LeCroy Corporation
is committed to providing unique, reliable, state-of-the-art instrumentation
in the field of high speed data acquisition and processing. Because of
the commitment, the Engineering Department at LeCroy is continually refining
and improving the performance of products. While the actual physical modifications
or changes necessary to improve a model's operation can be implemented
quite rapidly, the corrected documentation associated with the unit usually
requires more time to produce. Consequently, this manual may not agree
in every detail with the accompanying unit. There may be small discrepancies
that were brought about by customer-prompted engineering changes or by
changes determined during calibration in our Test Department. These differences
usually are changes in the values of components for the purpose of pulse
shape, timing, offset, etc., and, only rarely including minor logic changes.
Whenever original discrepancies exist, fully updated documentation should
be available upon your request within a month after your receipt of the
unit.
ANY APPLICATION OR USE QUESTIONS, which will enhance your
use of this instrument will be happily answered by a member of our Engineering
Services Department, telephone 914-578-6058 or your local distributor.
You may address any correspondence to:
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LeCroy Corporation
700 S Main St.
Spring Valley, New York 10977
ATTN: Customer Service Dept.
or
LeCroy Corporation
14800 Central S.E.
Albuquerque, New Mexico 87123
LeCroy Corporation
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1816 Holmes Street, Bldg. E
Livermore, California 94550
European Customers can contact:
LeCroy
Ltd.
LeCroy, SA
Elms
Court
101 Route DuNant-D'Avril
Botley
127 Meyrin 1-Geneve
Oxford OX2 9LP
England
Switzerland
LeCroy,
S.a.r.l.
LeCroy, GmbH
Avenue du
Parana
Werderstrasse 48
Z.A. De
Courtaboeuf
Postfach 10 37 67
F-91940 Les
Ulis, France
6900 Heidelberg
West Germany
A T T E N T I 0 N
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SEE SECTION 2 FOR A GUIDE TO INSTALL, POWER AND INITIALLY OPERATE THE
1440 SYSTEM.
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MODULES SHOULD NOT BE REMOVED OR PLUGGED IN WHILE THE UNIT IS TURNED
ON. DAMAGE MAY BE CAUSED BY MOMENTARY MISALIGNMENT OF CONTACTS.
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DO NOT OBSTRUCT AIR INTAKE.
IT IS IMPORTANT TO SET THE SIGN BIT FOR THE CORRECT POLARITY WHEN
REQUESTING HIGH VOLTAGE. IF 2500 (INSTEAD OF -2500) IS REQUESTED FROM A
NEGATIVE POLARITY UNIT THEN THERE WILL BE NO HIGH VOLTAGE OUTPUT.
SEE BACK POCKET IN BACK OF MANUAL FOR SCHEMATICS, PARTS LISTS AND
ADDITIONAL ADDENDA WITH ANY CHANGES TO MANUAL.
HV RESPONSE TO PROGRAMMING CHANGES IS IMMEDIATE WHEN HV IS ON. A
CHANNEL CAN GO FROM 0 V OUTPUT TO 2500 V OUTPUT IN LESS THAN 40 MSEC.
A T T E N T I 0 N
TABLE OF CONTENTS
SECTION 1 - SPECIFICATIONS
Technical Data Sheets
SECTION 2 - OPERATING THE 1440
2.1 Installation and Setup
2.1.1 Uncrating
and Inspection
2.1.2 Front
Panel Assemblies
2.1.2.1 1449 or 1449E
2.1.2.2 1445
2.1.2.3 1441
2.1.2.4 1442
2.1.2.5 1447
2.1.3 Rear Panel
Assemblies
2.1.3.1 Description
2.1.3.2 Calibration of 1443 Cards
2.1.4 Power
2.1.4.1 Supply Voltage
2.1.4.2 Connecting the AC Line Cord
2.1.4.3 Grounding
2.1.4.4 Initial Power Up
2.2 Communications with the
1440
2.2.1 BAUD
Rate
2.2.2 Cabling
2.2.3 Sign on
Messages
2.3 Startup Hints for
the 1440
2.3.1 Default
Settings
2.3.2 Control
Daisy Chain
2.3.3 Power
and Cooling
2.3.4 Optional
Hand Held Controller
2.3.5 Front
and Rear Panel Indicators of System 1440
Operating Status
2.3.5.1 Interlock
2.3.5.2 Status
2.3.5.3 Error
2.3.5.4 Fault
2.3.5.5 HV Enable/Panic Off
2.3.5.6 Pilot Lights
2.3.6 TTY --
Getting Started
2.4 Tutorial
2.5 1445 Full Scale Programming
Options
Figures for Section 2
SECTION 3 - CAMAC AND TTY CONTROL OF 1440
3.1 System 1440 ASCII Syntax of Command Lines
3.2 ASCII Line Parsing
3.3 Programmable Pointers
3.4 ASCII Instruction Set
3.4.1 Commands
3.4.2 Modifiers
3.5 Operations on Buffer Memories (Common to CAMAC and ASCII) 3.5.1 Copy
3.5.2 Swap
3.5.3 Update
3.6 CAMAC Control
3.6.1 Control
Commands - Short Form
3.6.2 Commands
Detailed Description
3.6.3 Responses
- Short Form
3.6.4 Response
- Detailed Description
3.7 General Notes on Using System 1440 with 2132 CAMAC Interface 3.7.1 Transmitting
to System 1440
3.7.2 Responses
from System 1440
3.7.3 CAMAC
Programming
3.7.4 Summary
of CAMAC Function Codes for 2132
Interface
SECTION 4 -- TECHNICAL DESCRIPTION
4.1 1445 Controller
4.2 1443 High Voltage
Cards
4.3 1442 Power Supply
4.4 1441 Power Supply
4.5 Output Current Characteristics
Figures for Section 4
Schematics and Addenda
HIGH VOLTAGE SYSTEM
MULTIPLE CHANNEL, HIGHEST
DENSITY
LeCroy
SYSTEM 1440
WITH LOCAL REMOTE CONTROL
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Up to 256 Channels Per Mainframe
Remote Control Via CAMAC or RS-232-C
Lowest Cost Per Channel
+ 2500 V, 2.5 mA Per Channel
Slow HV Ramp-up and Ramp-down
Short-circuit and Arc Protected
TTL System Interlock/HV Status Output
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FOR LARGE-SCALE PHOTOMULTIPLIER ARRAYS AND WIRE CHAMBER
SPECTROMETERS
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System 1440 is a multichannel programmable high voltage system designed
for large scale applications where high reliability and performance are
most important. The system provides up to 256 channels of high voltage
in each 1449 chassis. Up to 16 chassis, or 4096 channels, may be controlled
and monitored via a single daisy chain. Control may also be done
from CAMAC via the LeCroy Model 2132 CAMAC/HV Interface.
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FEATURES
Digital Voltage Sensing
A system ADC reads the actual output voltage, NOT the demand setting,
with 12-bit precision. The output polarity is also reported.
Complete CAMAC Programmability
All the operations which may be performed from the TTY are available
through the Model 2132 CAMAC interface. A simple binary control word scheme
makes programming easy.
Thermal Protection
A temperature monitor on each of the low voltage power supplies shuts
off the high voltage in the event of overheating that can result from excessive
loading, clogged fan filters, or high ambient temperatures.
Continuous Memory
Battery backup protects the integrity of internal memory for 24
hours. This makes the memory immune to occasional power failures. The batteries
are continuously recharged whenever AC power is available.
FUNCTIONAL DESCRIPTION
System 1440 employs high efficiency switching supplies. As a fourth
generation design, the HV supplies offer cool and reliable operation. The
system reliability is further enhanced by the design of the mainframe which
provides excellent cooling and a minimum of interconnects.
Convenience, versatility and serviceability have been achieved
through
the use of modular construction. The microprocessor circuit, the power
unit, two 31 V DC supplies and up to sixteen 16-channel HV supplies
plug
into the 1449 mainframe. As a result, the system can provide negative
outputs,
positive outputs, or both. Systems of less than 256 channels may be
easily
established. A more economical low power chassis, Model 1449E, is also
possible for those applications which require less than the full power
output of the unit. For details, see the ordering information listed
below.
System 1440 provides many features to protect its costly loads against
HV damage. The HV run-up and run-down rates may be selected by a jumper
option on the control unit. Rates of 0.5 -- 3.0 kV/sec are available. Rapid
shutdown (panic-off) of all channels is provided locally by a pushbutton
and also from a remote sensor via TTL System Interlock input. The 1449
chassis provides a clamp-to-ground output to indicate that the HV is on.
The 1443/12 HV module provides an interlock to disable all 16 channels
when the Card Interlock contacts are opened (available on block connector-type
modules only).
The 1449 mainframe has two vernier potentiometers to provide separate
hardware limits to set the maximum voltage output of the positive and negative
channels. Two 8-bit registers are available to provide separate software
limits for setting the output current limit threshold of the positive and
negative channels. The 1443/12 Series modules are available for both polarities.
To avoid problems caused by the use of modules of the wrong polarity, the
1443/12 treats a demand voltage of the wrong polarity as a 0 V demand.
As a second safeguard, output polarity indication is provided in the voltage
monitor readback.
System 1440 contains a 13-bit ADC (12 bits plus sign) to allow the
output voltage of all channels to be measured. The accuracy of the monitor
is +(0.1%+1.5 V). The voltage programmability of the HV modules is 12 bits
(plus sign bit).
The maximum output voltage available from the 1443/12 Series card is
2500 V. The full scale of the system programming may be jumper selected
to be 2500 V, 2047 V, 1500 V and 4095 V (2500 V maximum allowable demand
value). This allows the range and resolution of System 1440 to be matched
to the experiment requirement.
ORDERING INFORMATION
Mainframe 1449/1449E
To order a System 1440, it is first necessary to determine the
total HV power required for the application. For those systems requiring
less than 256 channels or those requiring less than full voltage and current,
the low power mainframe, 1449E, may suffice. If not, order the Model 1449
mainframe. Both versions include all logic and control units required for
use with up to 256 HV channels. The 1449 provides a total of 1.6 kW to
the 1443/12 HV cards. The Model 1449E provides 0.8 kW. For each 1443/12
card in excess of eight, 15 W must be deducted from the available 1449E
power.
Example: A system consisting of 176 channels, operating at 2 kV,
each with a load of 2 mA must provide: 176 x 2 kV x 2 mA = 704 W. Since
11 cards are required, 755 W are available from the 1449E so the lower
priced 1449E may be selected.
If the 1449E must be upgraded for 1600 W operation, a Model 1442 DC
Supply must be ordered. The time required to install and test the addition
is less than 1 hour. No special tools are required.
16-Channel IIV Modules 1443 Series
HV modules provide 16 outputs of up to 2.5 mA at 2500 V. Modules of
positive and negative output are available and are denoted by P and N suffixes,
respectively.
The HV modules employ front-panel block connectors for the 16 HV outputs.
Also available is the SHV connector by specifying an F suffix.
Model
1443N/12
Negative, block connector
Model
1443P/12
Positive, block connector
Model
1443NF/12
Negative, SHV connectors
Model
1443PF/12
Positive, SHV connectors
Model
1440X
Extender for 1443/12 Series
HV module and 1445
microprocessor unit. Intended
as a service tool.
Model
1441
Power module. Spare part. Included
in 1449 Series.
Model
1442
DC supply. Included in 1449 Series.
Model
1445
Microprocessor unit. Included in
1449 Series.
Model
1447
Handheld TTY.
Model
2132
Interface to CAMAC
CONNECTORS
Model
HVCK20FB
Female bulkhead type (used on
1443/12 front panel).
Model
HVCK20MB
Male bulkhead type.
Model
HVCK20FC
Female cable type.
Model
HVCK20MC
Male cable type (mates with
1443/12 front panel).
ACCESSORIES
CCHV16-M A data cable used to connect
the 1440 chassis to each other. M is the
length of the cable in meters.
CDHV16 M A data cable used to connect
the 1440 chain to a controller. A standard
RS-232-C 25-pin "D" connector is employed at the controller end. M is
the length of the cable in meters. See below for "D" connector
to adapter options.
AD/TTY Mates with CHV16
cable. Provides pigtails suitable for direct
connection to a Teletype.
AD/CAM Mates with CDHV16
cable. Provides the correct connector for
connection to the Model 2132 Interface to CAMAC.
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Handheld Controller
Optional Model 1447 handheld controller allows local control of
a 1449 chassis. By plugging the Model 1447 into the Auxiliary Control connector
of the 1449 chassis, commands can be issued to the chassis without interruption
of the other chassis in the control daisy chain. |
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Panic-Off
A front-panel pushbutton shuts down all supplies promptly for protection
against the unexpected.
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HV Status Output
A front-panel Lemo output used to indicate HV present at rear connectors.
May be used for personnel safety interlocks or as an independent indicator.
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Interlock
A front-panel BNC input accepts a TTL input, triggering a panic-off.
Internal programming jumper allows user assignment of logic levels, allowing
the input to be used as a failsafe interlock or a remote panic-off. |
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Error Indicator
A front-panel Lemo connector used to indicate that all HV channels
are operating within 1.5% (of F.S.). An error condition produces a TTL
clamp-to-ground. Empty stations within the mainframe are ignored for this
diagnostic. If the error is corrected, the Error Indicator output returns
to its quiescent open circuit condition. |
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Voltage Limit
Two front-panel adjustments set hardware limits separately for
positive and negative channels. |
Model 1443 16-CHANNEL HV MODULE
Each 1443 card has 16 independently controlled High Voltage outputs.
These cards may be ordered with block connectors or with SHV connectors
(F suffix) for the High Voltage outputs. |
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Sophisticated Interactive TTY Operation
A simple, easy to understand mnemonic language allows all of the features
of System 1440 to be exercised. This includes setting, measuring and adjusting
any channel or all channels. The language offers iterative command execution
similar to a FORTRAN DO Loop, allowing commands to operate on groups
of channels. The system can offer a status report and print out an array
of measurements of all outputs within the mainframe. Each mainframe must
be assigned a unique address. This allows commands to be referred to each
chassis. Special shorthand allows the addressing to be skipped after the
first reference. An RS-232-C type interface is used.
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Intelligent Daisy Chain
Up to 16 mainframes may be operated remotely. Serial Transmit and Receive
lines are used. An identifier line allows the system to differentiate between
CAMAC
and TTY modes. This allows for ASCII coding for TTY
operation and binary coding for CAMAC operation. Binary coding greatly
simplifies programming. The 1440 system automatically knows which remote
device is active.
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Fault Indicator
A front-panel connector signals a fault by a clamp-to-ground. A fault
condition is generated by a failure of any of the DC power supplies. The
most common causes are over-temperature or over-current conditions.
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SPECIFICATIONS
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Model 1449/1449E HV
CONTROL MAINFRAME
GENERAL
HV Modules/Mainframe: Up to 16
Channels/Mainframe: U p to 256
Maximum HV Output Power: 1.6 kW for Model 1449. 800 W for Model
1449E. For each 1443/12 in excess of eight, deduct 15 W from the 800 W
available.
DISPLAY
HV ON Indicators: Yellow lamp indicates HV is enabled for turn
on, i.e., HV DISABLE is not actuated and INTERLOCK is not asserted. Integral
with front-panel HV ON indicator (red lamp) and HV DISABLE button. Rear-panel
indicator lamp.
LVPS Status: Two LED's indicate presence of -- 15 V and + 5
V. Ready lit by + 15 V.
System Active: Front-panel LED indicates 1443/12 Cards enabled
for generating HV.
MECHANICAL
Packaging: 19" rack-mount chassis, 17" wide x 22" deep x 261/4"
high.
(Add
3" to depth to include handle protrusion.)
Input Power: 180-260 V AC 50/60 Hz <15 A.
Ambient Humidity: 0 to 85% relative humidity.
Operating Temperature: 10 to 40oC ambient.
Shipping Weight: 210 lbs. (95 kg).
Model 1443
16-CHANNEL HV MODULE
Channels/Module: 16
Output Voltage: 0 to 2500 V; > 500 V for rated performance.
Polarity indicated by
N or P suffix.
Voltage Regulation: 0.05% of full scale, line and load.
Full Scale: 2500 V, 2047 V, 1500 V; 4095 V also available
(limited to 2500 V max.) mainframe jumper option.
Programming Step: 0.025% of full scale.
Programming Accuracy: <+0.2% + 2 V) for demand voltages >
500 V.
Programming Reproducibility: < 1 V at a constant load and
temperature
after 10-minute warmup.
Voltage Monitor Accuracy: +(0.1% + 1.5 V) channel-to-channel.
Monitor Long-Term Stability: <1.5 V/wk at constant load and
temperature.
Output Long-Term Stability: <2 V/wk at constant load and
temperature.
Monitor Temperature Coefficient: Typically 0.005%/§C. Max.,
0.01%/§C
form 500 V to 2500 V (10oC to 40oC ambient).
Output Ripple: Typically <50 mV peak-to-peak; <250 mV
peak-to-peak maximum.
Current Output: Up to 2.5 mA per channel.
Output Protection: Fully protected against arcs at load, short
circuit and overload.
Output Connector Type: Multiconductor block-type connectors.
SHV connectors
specified by F suffix.
Model 1443 16
CHANNEL HV MODULE
BLOCK CONNECTOR DATA
PIN ASSIGNMENTS
PIN FUNCTION
1 HV Output Channel 0
2 HV Output Channel 1
3 HV Output Channel 2
4 HV Output Channel 3
5 HV Output Channel 4
6 HV Output Channel 5
7 HV Output Channel 6
8 HV Output Channel 7
9 HV Output Channel 8
10 HV Output Channel 9
11 HV Output Channel 10
12 HV Output Channel 11
13 HV Output Channel 12
14 HV Output Channel 13
15 HV Output Channel 14
16 HV Output Channel 15
17 Ground Return --
18 Ground Return
--
19 Interlock (short --
to 20 for enable)
20 Interlock (short --
to 19 for enable)
SECTION 2
OPERATING THE 1440
2.1 Installation and Setup
2.1.1 Uncrating
and Inspection
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The packaging for the 1440 System consists of a heavy cardboard box
and a wooden pallet held together by two steel bands. The 1440 container
should always be oriented with the pallet down. The package is custom made
for the system and should be saved for any subsequent shipments which may
be required. Rebanding requires the use of a banding machine, commonly
available in Shipping and Receiving departments.
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To open the box, cut the two bands and lift the cardboard box off of
the unit. The 1440 can be lifted off of the pallet, allowing the package
to be saved. Discard the bands.
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Inspect the 1440 System for signs of damage. If problems are found,
contact your nearest LeCroy office for assistance. The 1440 System employs
modular construction to aid in service and enhance system flexibility.
Check each of the subassemblies to be sure that it is seated in place and
that its captive securing screws are snug. The subassemblies that should
be checked are summarized in the following sections.
2.1.2 Front Panel
Assemblies (See Figure 2.1)
2.1.2.1 Model 1449 or 1449E are the
model numbers of the
mainframe including power supplies and control. The
1449-Series does not include the plug-in HV cards.
Inspect the structure for mechanical integrity. Front
panel units may be inspected by loosening their retaining
screws. The assembly will then pivot on its lower edge
as shown in Figure 2.2 and 2.3.
A "catch" will hold the
unit in the open position. The "catch" must be released
before closing the unit.
2.1.2.2 Model 1445 is the controller
for the unit. It is located
in the rightmost position in the front of the 1449. It is
a plug-in module. The front panel of the unit (see
Figure 2.4) provides communication connectors (both
the
control daisy chain and the optional hand held
controller), Fault and Error diagnostic outputs, power
supply and microprocessor pilot lights and a mainframe
address selection switch. On-board jumpers allow the user
to select the communication BAUD RATE, the voltage
programming full scale and the voltage readback full
scale. When the unit leaves the factory, these values are
set to 1200 BAUD, 4095 V and 4095 V respectively. For
details on reprogramming, see Figure 2.8.
2.1.2.3 Model 1441 is the Supply and
Control module. It is
located to the left of the Controller. The Model 1441
provides +15 V and +5 V. High voltage limit circuits for
both positive and negative supplies voltage run up and
run down circuitry, safety-interlock functions and the
line voltage monitor. The 1441 is hinged at the bottom
and may be accessed by unfastening the top two screws
and pivoting it out.
The front panel of the Model 1441 includes voltage limit
vernier potentiometers, and HV ENABLE (safety) button,
an HV STATUS indicator (TTL compatible) output and a
pilot light and an INTERLOCK input.
The Model 1441 contains jumpers to set the voltage run-up
rate, voltage run-down rate and the Interlock polarity.
These are factory set, respectively, to 1 KV/sec,
1 KV/sec and normal (not asserted when open). For details
on reprogramming, see Figure 2.5.
2.1.2.4 Model 1442 is a 1 KW DC supply
used to provide power to
the 1443 high voltage plug-in cards. The Model 1449
contains two of these units, located in the left two
compartments of the front of the unit. The right (center)
1442 station is vacant in the 1449E. The 1442 subassembly
does not include the front panel. Separately ordered 1442
for spares will be supplied without the front panel which
is part of the mainframe.
2.1.2.5 Model 1447 is a hand-held controller
(see Figure 2.6)
intended for local operation of the 1440 system. It is an
optional accessory not included in the 1449/1449E
package. When plugged into the 1447 input of the Model
1445, it overrides the control daisy chain to this unit
only. Other mainframes are unaffected by the
installation of the 1447.
2.1.3 Rear Panel
Assemblies
2.1.3.1 Description
Up to sixteen of the 1443-Series sixteen-channel high
voltage cards plug into the 1449 or 1449E mainframe.
Cards designed to provide outputs of negative or
positive polarity may be plugged into the unit without
regard to position in the chassis.
2.1.3.2 Calibration of 1443 Cards
Field calibration of the 1443 series HV Cards is easily
done with the panel accessable potentiometer on each HV
channel. The action of the potentiometer is to change the
monitor reading reported by the 1445 controller. Turning
the adjustment clockwise increases the magnitude of the
HV output. Typically the potentiometer allows about
+ 30 volts of adjustment.
The following procedure applies for each channel to be
calibrated.
1. Program a Demand voltage of + 2500 volts (depending
on card polarity).
2. Read actual output of the channel through the
mainframe monitor and note reading.
3. Measure actual HV output with an external metering
scheme and while monitoring adjust panel accessable
potentiometer to set the reading on the external
metering scheme to agree with that of the internal
ADC Monitor as done in step 2.
This assures that the internal ADC monitor agrees with
the actual HV output. By using the Update feature of the
1440 system, accuracy of the HV outputs can be improved
almost to the accuracy level of the internal monitor.
2.1.4 Power
2.1.4.1 Supply Voltage -- The 1449 mainframe
requires input
voltage from the line between 208 to 240 VAC 50 to 60 Hz.
This voltage can be applied either line-to-line or
line-to-neutral. Input line variations over the range of
180 to 260 VAC will be tolerated by the mainframe. A low
line detector in the 1441 disables internal power
supplies if the line drops below 180 VAC and internal
varistors clamp the input line from exceeding 265 VAC.
A fully loaded 1449 mainframe consums 2500 W from the
input line. Normally the maximum current drawn from the
line at full power varies from 9 to 13A, depending upon
input line voltage. A 16A circuit breaker is integral to
the main AC power switch on the front panel. It is
suggested that each 1449 mainframe be connected to its
own 20A power feed.
At 50 Hz output ripple specs will be met above 190 VAC.
At full rated power below 190 VAC the line frequency
ripple will grow and may exceed normal p-p ripple specs.
Mainframe will still shut down at 180 VAC.
2.1.4.2 Connecting the AC Line Cord
-- The 1449 mainframe is
supplied with a 3 conductor detachable 3 meter line
cord. Each conductor is 14 AWG. A foil shield surrounds
the 3 conductors and is attached to the ground wire in
the mainframe via the light gauge uninsulated wire. A
line plug is attached to the end of the power cord with
screw terminals. If it is necessary to change the line
plug, remove the 2 screws holding the plug together and
remove all three wires from the plug.
The 3 wires in the line cord are designated as follows:
BLUE
LINE
BROWN
NEUTRAL OR LINE
GREEN/YELLOW
GROUND
Note that the ground wire is also connected to the foil
shield to suppress radiated noise from the power cord.
2.1.4.3 Grounding -- Proper
grounding of the mainframe is
essential for proper mainframe and multi-mainframe
system operation. The High Voltage outputs and the
RS232C communications interface are referenced to
the 1449 mainframe chassis. The ground wire of the
line cord is also connected to the mainframe chassis.
Ground loops could cause spurious communications or
excessive line noise at the HV outputs. It is possible
to have substantial ground differences in an
experimental lab environment between different power
feeds and or the experimental high voltage load grounds.
Three phase power distribution systems are especially
susceptible to this phenomenon.
All 1449 mainframes, the CAMAC or RS232C communication
device and the HV load ground should be grounded together
with a good low inductance high current capability
conductor. The entire system should then be tied to a
good earth ground. The ground connection of the line plug
should be attached to the input power outlet if it is
essentially "clean" with respect to the system ground
established above. If the power outlet ground is "dirty"
with respect to the system ground then large ground
currents could flow and it would be advisable to not
make connection of the line cord ground to the wall
outlet ground.
2.1.4.4 Initial Power Up --
Once the line cord has been properly
installed to the wall outlet and the system has been
properly grounded, the system can be powered up and
checked out.
Turn on the AC main power switch by pressing the top
half of the rocker in. The switch should become
illuminated and the fans should be heard immediately.
A 2 second delay is implemented before the supply
voltages of the 1441 are allowed to turn on. After
this initial delay the "READY" portion of the HV ENABLE
switch on the 1441 and the 3 LEDS on the 1445
(-15, +5, ACTIVE) should all be lit.
Note that the HV on light is off. The 1440 always powers
up with high voltage off. Depress the HV enable switch
(a push-push type) and both the READY and ACTIVE lights
should go out. Depress the HV enable switch again and
both lights should turn back on.
2.2 Communications with the 1440
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2.2.1 BAUD
Rate
The BAUD rate of the 1440 system is factory set to 1200 BAUD.
Any
standard rate can be selected over the range 75 to 9600 BAUD. It
should be set to match the computer port or terminal to be used The
BAUD rate is set by a jumper within the Model 1445. See Figure
2.8.
Our RS232C format uses the following characteristics:
8 Bits,*
1 Stop Bit and
No Parity
*Note: was 7 bits for Prom versions 1.4 or lower
2.2.2 Cabling
A system containing multiple 1449 mainframes employs the CCHV16-M
cable to interconnect This cable must run from J2 on one 1440 to
J1 on the next as shown in Figure 2.9. These connectors
are located
on the Model 1445. This cable consists of standard ribbon cable
terminated at each end with 8-pair connectors. Here M is the length
of the cable in meters. See Figure 2.10.
An RS232 port on a computer or a standard terminal usually employs
a standard D type connector. To aid in connecting the 1440 System
to such a device, a CDHV16-M (M = length in meters "able is
available. This is a cable identical to the CCHV16-M at one end but
terminated in a mating D connector at the other end
(see Figure
2.11).
The total length of all of the cables in the control daisy chain
should be limited to 150M (500 feet).
To connect the control daisy chain to a Model 2132 interface or to a
teletype adapters are available as Models AD/CAM and AD/TTY
respectively (see Figures 2.12 and 2.13).
The AD/TTY cable makes
system 1440 compatible with terminals using a 20 mA loop.
The high voltage outputs of the 1443 cards may be either SHV or
block connectors Parts for both the male (HVCK-20MC) and female
HVCK-20FC) block connectors are available from LeCroy (see Figures
2.14 and 2.15). A summary
of the parts contained in these kits and
cross references with AMP part numbers is contained in the following
table.
2.2.3
Sign On Messages
In the ASCII communication mode the 1445 will generate a sign on
message when the internal microprocessor is initialized. If a 1447
is plugged in this message is "1447 OPERATIONAL"; the normal message
via the daisy chain is "LeCROY SYSTEM 1440". The messages are
normally generated on AC power up. Also any time that the 1441
detects more than 1 missing AC line cycle it will recycle the
internal power supplies and generate the sign on message. Whenever
the internal power supplies are cycled the microprocessor sets the
HV status to OFF. This is a useful indication that the AC power line
is noisy and the situation should be investigated.
In the unlikely event that the microprocessor stops properly
executing it's microprogram a hardware circuit will reset the
microprocessor and a sign on message will be generated. Since
this reboot was not caused by a loss of AC power no change in the
operating status of the 1440 system will occur (HV will remain on if
it was on for example) except that the mainframe select command may
have to be reissued. The Z command (system reboot) has the same
actions as those just described.
HV BLOCK CONNECTOR PARTS AVAILABLE
LRS
#
AMP #
Male Connector Pin
(1)
405-463-003
201330-1
Connector Block
(1)
405-463-003
203908-2
Male Guide Pin
(2)
405-213-001
200833-4
Female Guide Pin
(2)
405-343-004
200835-4
Male Jackscrew
(2)
405-260-001
226654-2
Female Jackscrew
(2)
405-370-001
226655-1
Shield (Special)
(2)
201846-1
Shield (Standard)
(2)
405-691-008
201571-1
Connector Block
(3)
405-152-002
203909-2
Female Connector Pin
(3)
405-545-001
201328-1
(1) For use
on male connectors only (mates with 1443 front panel)
(2) For use
on either male or female connector ends
(3) For use
on female connectors only
Parts (1) and (2) are contained in connector kit HVCK-20MC. Parts (2)
and (3) are
contained in kit HVCK-20FC.
Recommended HV wire (3 kV rating): LRS #589-601-124
ITT #VU1029-9-C
2.3 Startup Hints for the 1440
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2.3.1
Default Settings
As delivered, the 1440 will be set to:
l. Range -- 4095 V full scale which corresponds to 1
V/count. If
demand exceeds 2500 V, the hardware voltage limit will
override. Note: some modules have 12-bit DACs and some have
10-bit, however all programming is done to 12-bits. For 10-bit
channels, the two LSB's -are ignored by the HV card. Therefore
High Voltage will be incremented in minimum steps of 4 volts
(4V/4 counts rather than 1V/1 count) in 10-bit modules.
2. BAUD rate -- 1200 BAUD. When communicating with either
the
Model 1447 optional hand held controller or with the Model
2132 CAMAC interface, the 1440 System automatically adjusts
its BAUD rate accordingly. With other terminals, check that the
BAUD rate matches the terminal. See Figure 2.8. This
unit uses
RS232C so it is directly compatible with most commercial
terminals. The pin outs of the communication daisy chain
connectors on the 1445 are shown in Figure 2.16.
3. Run-up and run-down rates set to 1 KV/sec.
2.3.2 Control
daisy chain -- uses 16-wire ribbon cable. See Figures
2.9, 2.10
2.11, 2.12, 2.13.
Last mainframe need not be terminated.
2.3.3 Power
and Cooling -- Operates off nominal 208 or 220 V, 50 or 60 Hz.
Filters for fans which cool the system are easily removed for
cleaning as shown in Figure 2.17.
2.3.4 Optional
hand held controller, Model 1447, -- when plugged in,
overrides that 1449 mainframe but others in chain remain active.
2.3.5 Front
and Rear Panel Indicators of System 1440 Operating Status
2.3.5.1 INTERLOCK: TTL level input, edge triggered.
Polarity is
user selectable. When triggered INTERLOCK immediately
stops the 1443 cards from generating voltage. Shortly
thereafter the processor will turn off the 31 V supplies
and return the system to the OFF state.
2.3.5.2 STATUS: TTL level output. Open collector,
diode isolated
(high impedance when AC off). HV on is indicated by a
clamp to ground.
2.3.5.3 ERROR: TTL level output. Open collector,
diode isolated.
The processor monitors the actual output from all channels
in the mainframe (only while HV is on). If any channel is
in error by more than 64 counts the ERROR output is
clamped to ground, when the channel(s) are no longer
in error the output is released. This condition will
always exist during a HV turnon and the release of
ERROR may be used to indicate end of turn on.
2.3.5.4 FAULT: TTL level output. Open collector, diode
isolated.
The clamp to ground indicates that one or more of the AC
supplies is shut down. This condition may be caused by
overtemperature, overcurrent, or other reasons. The
processor attempts to clear all but a fault from the +5
volt supply. The +5 supply will try to clear itself. As
a result of the processors attempts to clear a fault, the
output may be pulsed. This is due to the interactive
nature of the fault and reset conditions. When the reset
is issued the supply will attempt to turn on. During this
time it may not be in fault. For example, overcurrent will
not exist until a certain output voltage is achieved,
whereas over-temperature may exist for a long time.
2.3.5.5 HV ENABLE/PANIC OFF: Push button "flip flop"
switch.
Pushing the switch initiates the same sequence as
INTERLOCK. However, in order for the 1440 to resume
generating voltage, the switch must be pushed a second
time. The yellow HV READY light will be lit when the
unit is able to generate voltage.
2.3.5.6 Pilot Lights: The 1440 System contains several
pilot
lights which give a visual indication of certain
operating conditions.
+5 LED -- Indicates +5 is functional.
-15 LED -- Indicates -15 is functional. +15 operation
can be verified by the HV READY lamp. Both
+15 and -15 should be tracking with both on
or both off.
ACTIVE LED -- Indicates that 1443s are receiving sync
pulses. The 1443s cannot generate voltage
without a sync pulse.
READY -- Indicates that HV may turned on. When off HV
cannot be turned on.
HV ON Lamp -- Indicates that controller has enabled 31
V supplies and that HV is on.
31 V Pilot lamp -- Located on the rear of the unit.
Provides a visual indication that
the 31 V supply is operating.
2.3.6 TTY
-- getting started:
Steps 1 and 2 should be omitted when using the 1447.
1. Set and note mainframe address to XX via rotary switch on 1445.
No specific value is required.
2. Enter " MXX (CR) " to select unit MXX.
3. Enter " W2500 CO A (CR) ". This writes a demand of +2500 V to
All channels. Insert a "-" sign after the "W" if negative high
voltage is desired. Here A indicates All. Addressing of the
Demand register is caused by reference to CO.
4. Enter " ON (CR) " Turn on HV
5. Enter " R E A (CR) " note spaces between R, E and E, A. Read
out Every value for All channels i.e., measured voltage and
Demand and Backup programming registers voltages for all
channels. (Note cntl C aborts if you get impatient).
6. If the desired high voltage does not appear on the outputs,
check:
a. Actual and Demand Polarities (check the printout from
Step 5) must match (see Step 3). Cards will not generate
voltage if the wrong polarity is requested.
b. If the 1443 cards supplied with the system, have block
connectors, the HV Interlock must be grounded to generate
high voltage (Pin 19 connected to Pin 20 -- see
Figure 2.18). For testing and tutorial a 10 G 1/4
watt
resistor may be used on card 0 (caution HV will be exposed).
c. Current limit must be programmed to provide current
sufficient for any loads plugged into the 1443 cards (see
TTY instructions SECTION 3).
d. 1441 front panel voltage limits (positive and negative)
must be set high enough to allow the programmed voltage.
e. HV must be enabled. Yellow Ready light should be lit.
If not, push switch.
f. Verify light on rear panel is on. If not check setup of
31.5 V supplies. The back plane power bus is split such
that each 1442 supplies 8 cards. The 1449E has both buses
connected together. Verify appropriate connectors for the
number of 1442's by removing 1443 card 7 and visually
inspecting (as shown in Figure 2.19). The jumpers
may be
installed, if needed, by top soldering. Clearance behind
the board is only .25 inches.
2.4 Tutorial
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Start up 1440 as discussed in Section
2.1. All channels should be at + or
-- 2500 V. No sensitive equipment
should be connected until the user is
familiar with the system.
The following commands demonstrate some
of the features of the 1440.
1. Enter "CO U N(CR)". Copy the
Demand to the Backup and uses the Backup
to compensate
(Update) for tolerances in the Backup Demand.
The N reports any
channels that do not meet allowable tolerance. The
unit should respond
with "NONE".
2. Enter "R F V CO,ODO16(CR)".
Unit will respond with actual voltage
readings for all
channels on card 0. Substituting P for V in this
command would
cause a response showing the Demand Programmed Voltages.
3. Enter "W 1400 C5DO4(CR)".
If the first 1443 card is an N model, the
command should
be "W-1400C5DO4(CR)". This will set 4 channels (5, 6,
7 and 8) to 1400
volts. This may be verified by entering "R P DO4(CR)".
The channel number
does not need to be respecified. The Demand buffer
will be read since
it was operated on by the previous command.
4. Enter "I1000C7DO10R(CR)".
Unit will respond with "Reading Channel
C17 DEM XXXX"
which means that channels 7-16 have been set to 1000 V,
channel 17 is
left at voltage XXXX and the pointer is at Channel 17.
This is the most
convenient method to sequentially set all voltages in
a system to differing
values.
At this point it is
recommended that the user read Section 3 and
practice the commands.
2.5 1445 Full Scale Programming
Options
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See Figure2.8.
Full Scale
Volts/Count*
10 Bit Card
(approx)
(Exact)
Programming Step
4095
1.000
4 V
2500
0.625
2.5 V
2048
0.500
2.0 V
1500
0.375
1.5 V
*12 Bit System Programming
Example of 10 Bit vs 12 Bit Programming at 1.000 Volts/Count
10 Bit
Programmed
Voltage
Demand
Monitor
2046
2044
2047
2044
2048
2048
2049
2048
2050
2048
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Figure 2.1
|
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Figure 2.2
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Figure 2.3
|
 |
Figure 2.4
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