CAEN

Tools for Discovery

n Electronic Instrumentation

Rev. 16 - 01 Augst 2019

Es

A251x Series 50W LV Boards User Manual

Rev. 16 - 01 Augst 2019
Purpose of this Manual
This document is the A251x Series 50W LV Boards User Manual; it contains information about the installation, the
configuration and the use of the boards.

Change Document Record

Date Revision Changes
26 May 2014 0 PRELIMINARY Release
26 June 2014 1 Updated parameters p.15
9 September 2014 2 New PID coefficient description
3 February 2015 3 RTN – GND Isolation increased to ±500V
7 September 2015 4 Output control and monitoring parameters updated
23 October 2015 5 Technical Specifications updated
20 November 2015 6 Validated version
12 February 2016 7 Technical Specifications updated
25 May 2017 8 Output control and monitoring parameters updated
25 September 2017 9 Instructions for channels in series added
1 October 2018 10 Instructions for sense lines usage and channel reset
7 December 2018 11 Technical Specifications updated
22 January 2019 12 Technical Specifications updated
14 May 2019 13 Added data for A2517BA
10 July 2019 14 Updated External connections
22 July 2019 15 Added data for A251xC
01 August 2019 16 Technical Specifications updated

Symbols, abbreviated terms and notation

N.A.

Reference Documents
Disclaimer
No part of this manual may be reproduced in any form or by any means, electronic, mechanical, recording, or otherwise,
without the prior written permission of CAEN SpA.
CAEN will repair or replace any product within the guarantee period if the Guarantor declares that the product is
defective due to workmanship or materials and has not been caused by mishandling, negligence on behalf of the User,
accident or any abnormal conditions or operations.
CAEN declines all responsibility for damages or injuries caused by an improper use of the Modules due to negligence on
behalf of the User. It is strongly recommended to read thoroughly the CAEN User's Manual before any kind of operation.
CAEN reserves the right to change partially or entirely the contents of this Manual at any time and without giving any
notice.
Disposal of the Product The product must never be dumped in the Municipal Waste. Please check your local regulations
for disposal of electronics products.
Made In Italy : We stress the fact that all the boards are made in Italy because in this globalized world, where getting
the lowest possible price for products sometimes translates into poor pay and working conditions for the people who
make them, at least you know that who made your board was reasonably paid and worked in a safe environment. (this
obviously applies only to the boards marked "Made in Italy", we cannot attest to the manufacturing process of "third
party" boards).
 CAEN Electronic Instrumentation

Index
1. A251x Series Overview ....................................................................................................... 4
2. Channel Characteristic Table............................................................................................... 5
Characteristics of A2517BA, A2517, A2518, A2519 .................................................................................................. 5
Characteristics of A2517C, A2518C, A2519C ............................................................................................................ 6
3. Technical description .......................................................................................................... 7
Front Panel................................................................................................................................................................ 7
External connections ................................................................................................................................................ 8
Output connectors .................................................................................................................................................................8
Service connector...................................................................................................................................................................8
Interlock operation ................................................................................................................................................................9
Status operation .....................................................................................................................................................................9
Sense Lines .............................................................................................................................................................................9
Channels in parallel................................................................................................................................................. 10
Channel in series ..................................................................................................................................................... 12
4. Safety and installation requirements ................................................................................ 14
General safety information..................................................................................................................................... 14
Injury Precautions ................................................................................................................................................................14
Safety Terms and Symbols on the Product ............................................................................................................. 14
Installation .............................................................................................................................................................. 14
5. Operating modes .............................................................................................................. 15
Output control and monitoring .............................................................................................................................. 15
Proportional–integral–derivative (PID) controller .................................................................................................. 16

List of Figures
Fig. 1 – A251x series front panel (8 pin & db 37 version) ........................................................................................................................7
Fig. 2 – A251x with paralleled channels.................................................................................................................................................12
Fig. 3 – Schematic view of A251x channels in series .............................................................................................................................12
Fig. 4 – PID coefficients setting ..............................................................................................................................................................17

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1. A251x Series Overview

The Mod. A251x series are single width (5 TE wide) boards housing 8 LV floating channels, compatible
with the CAEN Universal Multichannel Power Supply System (SY1527, SY2527, SY4527, SY5527). The
floating return allows on-load grounding reducing the noise level; the floating channels are insulated from
each other and from Ground up to ±500 V.
Each output channel is provided with individual remote sensing lines to compensate for the voltage drop
over the connection cables
The Maximum channel power (connector output) is 50 W (1.25W for A2517BA). Channels can be
connected in parallel with modularity 2 or 4 to obtain higher output power (for 2/4 modularity Iset
resolution is 100 mA and Imon resolution is 10 mA); this feature is not available on A2517BA and on
A251xC versions.
The available versions are the following:

Version A2517 A2517BA A2518 A2518A A2519 A2519A

Output Voltage 1÷5 V 1÷5 V 3÷8 V 3÷8 V 5÷15 V 5÷15 V
Max. Output Current 15 A 250mA 10 A 10 A 5A 5A
Output Connector DSub8 DB37 DSub8 DB37 DSub8 DB37

The Output Voltage RAMP-UP and RAMP-DOWN Times may be selected independently for each channel
in the 1 ÷ 200 ms range (1 ms step).
Safety features include:
OVERVOLTAGE: if a channel monitored voltage goes above the programmed Overvoltage threshold value
(OVVThr), it is signalled to be in "overvoltage" and is switched off.
UNDERVOLTAGE: when the monitored voltage goes below the programmed undervoltage threshold
(UNVThr), the channel is switched off
OVERCURRENT: if a channel tries to draw a current larger than its programmed limit, it is signalled to be
in "overcurrent" and is switched off. In the A2517BA and A251xC versions, when overcurrent is detected,
the relevant channel can be programmed either to turn off after a programmable trip time or to keep on
providing the maximum allowed current: this feature allows the module to work as current generator.
FAST RAMP DOWN (A251xC): a faster ramp-down speed could be needed to better drive loads, such as
DC-DC converters, that otherwise would remain ON longer or enter ON-OFF cycles as the power supply
ramps down. The standard A251x’s are capable of ramping-down from full power to zero their channels
between 20 and 200 ms (less only with certain loads) while the A251xC’s can reach 1 V in 100 µs and
switch-off completely the channel in 1 ms in all conditions.
The output channels can be enabled according to the interlock logic (see Interlock operation)
A global enable/disable connector allows to disable the channels and it is also possible, via front panel
logic signals, to enable individually each channel (only for DB 37 versions).
Channels are organized into groups, and the turning on/off of the channels within one group can be
delayed up to 900ms (User programmable) between each other.
Channels feature a PID (proportional integrative-derivative) digital controller, whose parameters are User
programmable; in this way, the control loop can be optimized to any load (see also the Application Note
A251X Board Family PID Digital Regulation System, that can be downloaded from the A251x page at
www.caen.it web site).

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2. Channel Characteristic Table

Characteristics of A2517BA, A2517, A2518, A2519
Version A2517BA A2517 A2518 A2519

Packaging 1 unit (5 TE) wide, 6U-high mechanics

No. of Channels 8 (Individual Floating)

Polarity Floating

Output Voltage 1÷5 V (connector output) 3÷8 V (connector output) 5÷15 V (connector output)

Voltage Typical < 5 mVpp < 10 mVpp

Ripple Maximum < 10 mVpp < 20 mVpp

Max. Output Current 250mA 15 A 10 A 5A

Max. Ch. Output Power 1.25 W 50 W (firmware limited)

Minimum Load 0A

Voltage Set Resolution 1 mV

Vset Accuracy < ±0.5%

Voltage Monitor Resolution 0.2mV 1 mV (connector and status)

Current Set Resolution 100µA 10 mA; 100 mA (2/4 modularity)

Current Monitor Resolution 10µA 1 mA ; 10 mA (2/4 modularity)

Over/Under voltage thr. 0÷6 V settable for each channel 2÷9 V settable for each ch. 4÷16 V settable for each ch.

Over/Under voltage thr. Res. 10 mV

Accuracy Typical Maximum Typical Maximum

Vset vs Vout <± 0.1% ± 10mV <± 0.2% ± 20mV <± 0.1% ± 5mV <± 0.2% ± 10mV

Vmon vs Vout <± 0.1% ± 10mV <± 0.2% ± 20mV <± 0.1% ± 5mV <± 0.2% ± 10mV

Imon vs Iout <±0.2% ± 250µA <±0.5% ± 500µA <±1% ± 10mA <±2% ± 20mA

Iset vs Iout <±1% ± 1mA <±2% ± 2mA N.A.

Hardware OVV Protection 7.50V 9.75V 17.50V

Short Circuit Protection Available

Max. time an "overcurrent" can last (seconds). A Not Available

channel in "overcurrent" works as current
generator; output voltage varies to keep the output
current at the programmed value (if Vout > 0.7V).
"Overcurrent" lasting more than set value (1 to
9999) causes the channel to "trip". Output voltage
Trip
will drop to zero either at the Ramp-down rate or
at the fastest available rate, depending on Power
Down setting; in both cases the channel is put in the
off state. If trip= INFINITE, "overcurrent" lasts
indefinitely. TRIP range: 0 ÷ 999.9 s; 1000 s =
Infinite. Step = 0.1 s

Ramp Up/Down Time 1÷200 ms ; 1 ms step

Turn on/off delay 0 ÷ 900ms

Transient response Adjustable via PID controller

RTN – GND Isolation ±500V

Sense cable input impedance 1 kOhm

Enable inputs Available

Status outputs Available

Temperature range 0 ÷ 45 °C

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Characteristics of A2517C, A2518C, A2519C

Version A2517C A2518C A2519C

Packaging 1 unit (5 TE) wide, 6U-high mechanics

No. of Channels 8 (Individual Floating)

Polarity Floating

Output Voltage 1÷5 V (connector output) 3÷8 V (connector output) 5÷15 V (connector output)

Voltage Typical < 5 mVpp < 10 mVpp

Ripple Maximum < 10 mVpp < 20 mVpp

Max. Output Current 15 A 10 A 5A

Max. Ch. Output Power 50 W (firmware limited)

Minimum Load 0A

Voltage Set Resolution 1 mV

Vset Accuracy < ±0.5%

Voltage Monitor Resolution 1 mV (connector and status)

Current Set Resolution 10 mA

Current Monitor Resolution 1 mA

Over/Under voltage thr. 0÷6 V settable for each channel 2÷9 V settable for each ch. 4÷16 V settable for each ch.

Over/Under voltage thr. Res. 10 mV

Accuracy Typical Maximum

Vset vs Vout <± 0.1% ± 5mV <± 0.2% ± 10mV

Vmon vs Vout <± 0.1% ± 5mV <± 0.2% ± 10mV

Imon vs Iout <±1% ± 10mA <±2% ± 20mA

Iset vs Iout N.A.

Hardware OVV Protection 7.50V 9.75V 17.50V

Short Circuit Protection Available

Max. time an "overcurrent" can last (seconds). A channel in "overcurrent" works as current generator; output voltage
varies to keep the output current at the programmed value (if Vout < Vset min, the correct operation is not guaranteed).
"Overcurrent" lasting more than set value (1 to 9999) causes the channel to "trip". Output voltage will drop to zero either
Trip
at the Ramp-down rate or at the fastest available rate, depending on Power Down setting; in both cases the channel is
put in the off state. If trip= INFINITE, "overcurrent" lasts indefinitely.
TRIP range: 0 ÷ 999.9 s; 1000 s = Infinite. Step = 0.1 s

1÷200 ms ; 1 ms step. If Ramp Down is set to 0 (fast ramp down mode), the channel output will decrease to 1 V in 100µs
Ramp Up/Down Time
and turn off completely in 1ms

Turn on/off delay 0 ÷ 900ms

Transient response Adjustable via PID controller

RTN – GND Isolation ±500V

Sense cable input impedance 1 kOhm

Enable inputs Available

Status outputs Available

Temperature range 0 ÷ 45 °C

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3. Technical description
Front Panel

Fig. 1 – A251x series front panel (8 pin & db 37 version)

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External connections
Output connectors
WARNING! Despite Low Voltage, the risk of electric shock still exists; never connect or disconnect the Output
connector with the SYx527 power ON/OFF switch ON; always switch SYx527 power OFF and wait at least 30s before
connecting or disconnecting output cables.
A251x A251xA

DC8W8SA00LF D-Sub 8W8; cable connector: FCI DCPV37S300GT DB37; cable connector: Amphenol FCI
Amphenol FCI DC8W8PA00LF; available pin: DC37P064TXLF
PIN 10A Amphenol FCI 8638PPS1005LF; PIN
15A Amphenol FCI 8638PPS1505LF; PIN 20A Out Channels (0÷3; 4÷7) Positive, Negative; Sense± (0÷3;
Amphenol FCI 8638PPS2005LF 4÷7)

Out Channels (0÷3; 4÷7); Positive, Negative

Service connector
A251x A251xA

Type: FCI ICD26S13E4GV00LF D-Sub SKT 26 POS 2.28mm; cable connector: Amphenol FCI 10090769-P264ALF

Group Interlock (insulated); Group Status (insulated); Group Interlock (insulated); Group Status (insulated);
Sense± (0…3; 4…7); VAUX, DGND Individual Interlock (GND); Individual Status (GND);
VAUX, DGND

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Interlock operation
A251x
One Group (channels 0..3 and 4..7) can be ENABLED in one of the following ways:
− Short circuit IT- with DGND and IT+ with VAUX pins on service connector
− Send signal 4÷6V, ~5mA current between IT- and IT+
A251xA
One Group (channels 0..3 and 4..7) can be ENABLED in one of the following ways:
− Short circuit IT- with DGND and IT+ with VAUX pins on service connector
− Send signal 4÷6V, ~5mA current between IT- and IT+
One channel can be ENABLED in one of the following ways:
− Short circuit IT# with VAUX pins on service connector
− Send signal 4÷6V, ~5mA current between IT# and DGND

Status operation
A251x
− Contact closed between ST+ and ST- when no FAIL is present on one Group channel (0..3 and 4..7)
− Contact open between ST+ and ST- when FAIL is present on one Group channel (0..3 and 4..7)
A251xA
− Contact closed between ST+ and ST- when no FAIL is present on one Group channel (0..3 and 4..7)
− Contact open between ST+ and ST- when FAIL is present on one Group channel (0..3 and 4..7)
− Level high on ST# when no FAIL is present
− Square wave (TTL grounded) on ST# when FAIL is present

Sense Lines
Output channels have Sense Lines (see p.8) to compensate for the voltage drop over the cable. Voltage is
monitored directly at the load by a high input impedance differential amplifier through the sense wires.
When the sense wires are connected to the load, the Vset value equals the voltage on the load; if the
sense wires are not used, they must be left not connected, and Vset will equal the voltage on the
connector.

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Channels in parallel
N.B.: this feature is not available for Mod. A2517BA and A251xC
The A251x boards are provided with six Connection Keys (four X keys and two Z keys), that allow to
connect the channels in parallel.
The X key allows to parallel two channels, the Z key allows to parallel four channels.
As two or four channels are paralleled, the system automatically recognizes the actual number of
channels: two or four paralleled channels are seen by the control software as one channel with double or
quadruple output current and power.
In order to connect the channels in parallel, follow these steps:
• Remove ONLY the screws as indicated (orange circles)

• Remove carefully the shield

• Insert the Connection Keys between the channels to be paralleled
o Each connection key is provided with 2x3 pin male strips (two for X keys and four for Z
keys)

X key Z key

o The 2x3 strips must be plugged into the relevant sockets on A251x (named J20÷J27, see
figure)

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• Secure the Connection Keys with the provided screws, grover washers, flat washers

All adjacent channels can be paralleled, with the exception of Channel 3 and 4. The pictured configuration
shows:
• Channels 0-1 paralleled
• Channels 2-3 paralleled
• Channel 4-5-6-7 paralleled
With this configuration the SYx527 system detects 3 channels (0, 2, 4); the lower channel index is assigned
to the paralleled channels.

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Fig. 2 – A251x with paralleled channels

Once the Connection Keys are secured, it is possible to put the shield in place.
Remember that, at this point, it is necessary to short circuit the paralleled channels output; these
connections must be made as close as possible to the connectors, for both positive and negative voltages.
The same procedure is necessary for the Sense terminals.

Channel in series
It is possible to connect two channels in series; the control software will still manage them as separate
channels. The best performance is achieved setting the same VSET value on both channels (for example,
12V, to provide a 24V output); it is very important that ISET is smaller than 2A, on both channels.

Fig. 3 – Schematic view of A251x channels in series

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The figure above shows how to connect Ch0 with Ch1; the short connection must take place as close as
possible to the board output connector. The sense terminals Ch1+ and Ch0- are not used. If necessary,
the User can connect to the load the Ch0+ and Ch1- sense terminals.
It is very important to turn ON and OFF the channel in series at the same time; to do this, after assigning
the same index of “ChToGroup” parameter to both channels, the User can use the "OnGroup" and
“OffGroup" board parameters to turn them ON and OFF.

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4. Safety and installation requirements

General safety information
This section contains the fundamental safety rules for the installation and operation of the board. Read
thoroughly this section before starting any procedure of installation or operation of the product.

Injury Precautions
Review the following precautions to avoid injury and prevent damage to this product or any products
connected to it. To avoid potential hazards, use the product only as specified. Only qualified personnel
should perform service procedures.
Avoid Electric Overload.
To avoid electric shock or fire hazard, do not power a load outside of its specified range.
Avoid Electric Shock.
To avoid injury or loss of life, do not connect or disconnect cables while they are connected to a voltage
source.
Do Not Operate Without Covers.
To avoid electric shock or fire hazard, do not operate this product with covers or panels removed.
Do Not Operate in Wet/Damp Conditions.
To avoid electric shock, do not operate this product in wet or damp conditions.
Do Not Operate in an Explosive Atmosphere.
To avoid injury or fire hazard, do not operate this product in an explosive atmosphere.
Do Not Operate With Suspected Failures.
If you suspect this product to be damaged, have it inspected by qualified service personnel.

Safety Terms and Symbols on the Product

These terms may appear on the product:
DANGER indicates an injury hazard immediately accessible as you read the marking.
WARNING indicates an injury hazard not immediately accessible as you read the marking.
CAUTION indicates a hazard to property including the product.
The following symbols may appear on the product:
DANGER WARNING
High Voltage Refer to Manual

Installation
The A251x are single-width boards. At power ON the SYSTEM, the processor will scan all the slots in the
crate to find out where the module is plugged and what kind of module it is.

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5. Operating modes
The A251x boards can be controlled, either locally or remotely, through the SYx527 System software
interface. For board installation and details on SYx527 System operation, please refer to the User's Manual
of this product. The following sections contain a description of commands available for the board control
and status monitoring.

Output control and monitoring

The following board parameters are available:
Parameter Descritpion
BdStatus (monitor) bit 0: PowerFail; if 1, failure in the channels local power supply
bit 1: Firwmare Checksum Error; if 1, error in the board firmware checksum
bit 2: HVMax Calibration Error; if 1, the board HVMax parameter (if present) is not calibrated
bit 3: Temperature Calibration Error; if 1, the board temperature sensor (if present) is not calibrated
bit 4: Under Temperature; if 1, the board temperature sensor (if present) signals a board temperature < 5 °C
bit 5: Over Temperature; if 1, the board temperature sensor (if present) signals a board temperature > 65 °C
bits 6..31: Reserved
OnGroup (settable) Turn ON channel associated to the selected group
OffGroup (settable) Turn OFF channel associated to the selected group
Intck A (settable) Enable /disable operation of IT+/IT- signals of section A
Intck B (settable) Enable /disable operation of IT+/IT- signals of section B

For each output channel, the following parameters are available:

Parameter Descritpion
CHANNEL NAME (settable) Descriptive name for the relevant channel
V0SET (settable) Output voltage programmable value (make sure it is between UNVTHR and OVVTHR)
I0SET (settable) Current limit programmable value
UNVTHR (settable) Set output under voltage threshold
OVVTHR (settable) Set output over voltage threshold
RUpTime (settable) Set voltage ramp-up time
RDWnTime (settable) Set voltage ramp-down time. A251xC: 0 = FAST MODE
TRIP (settable): Set TRIP parameter value, i.e. the maximum time an Over Current condition can last. (A2517BA, A251xC)
VMON (monitor) Monitored voltage value
VCON (monitor) Monitored connector voltage value
IMON (monitor) Monitored current value
STATUS (monitor) Displays the channel status
PW (ON/OFF) Power parameter shows the ON/OFF channel status; when set to ON, the channel is switched on (if the
INTERLOCK is not active and if the channel is enabled either locally or remotely)
TripInt (settable) 2N-bit word (Dec. 0÷2^2N-1) max 16 lines, where N is the number of the board’s Internal Trip Bus lines.
Bits [0;N-1] allow the channel to sense the trip status from the corresponding lines when set to one; in
the same way, bits [N;2N-1] allow the channel to propagate the trip status over the Trip Bus: bit N on
line 0 and so on (see SY4527 User’s manual)
TripExt (settable) Must be set in the 0÷255 range. Bits [0;3] allow the channel to sense the trip status from the
corresponding lines when set to one; in the same way, bits [4;7] allow the channel to propagate the trip
status over the trip bus: bit 4 on line 0 and so on (see SY4527 User’s manual)
ONGRDEL (settable) Set ON delay between channel in the same group
OFFGRDEL (settable) Set OFF delay between channel in the same group
CHTOGROUP (settable) Number of group to associate the channel
TEMP (monitor) Monitored channel temperature
Intck Enable/Disable operation of channel interlock signals (only A251xA versions)

All parameters can be changed when the channel is off. When the channel is switched on, only a variation
of VSET in a range of ± 5% is allowed, for adjustment purposes.
To ensure that two or more channels are turned on / off with delays programmed by user, these channels
must be assigned the same value of the ChToGroup parameter and the desired time must be entered in

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the OnGrDel and OffGrDel parameters (0 = no delay). The switching on and off are performed by entering
the ChToGroup parameter value in the field OnGroup / OffGroup, (available as parameters of the board).
The following messages may be returned by the SYSTEM when monitoring the channel status:
OFF (channel turned OFF)
OVC (channel in OVERCURRENT condition)
OVV (channel in OVERVOLTAGE condition)
UNV (channel in UNDERVOLTAGE condition)
EXTTRIP (channel OFF due to external TRIP line signal) 1
INTTRIP (channel OFF due to internal OVERCURRENT condition)
EXT_DIS (channel disabled by board INTERLOCK protection)
PWR_FAIL (channel OFF due to a Power failure)
OVV_PROT (channel with connector over voltage detected)
TEMP_ERR (channel over >85°C / under <5°C temperature)
After an ALARM notification, it is necessary to perform a CLEAR ALARM cycle, before turning the channel
ON. If, after the CLEAR ALARM cycle, voltage and/or current monitored values still exceed the channel
range by more than 10%, then it is necessary to perform a Power Cycle over the board.

Proportional–integral–derivative (PID) controller

The channels implement a digital type PID controller, a feedback control loop algorithm that involves
three separate parameters; the Proportional, the Integral and Derivative values.
The Proportional value determines the reaction to the current error, the Integral determines the reaction
based on the sum of recent errors and the Derivative determines the reaction to the rate at which the
error has been changing.
The weighted sum of these three actions is used to adjust the process via the control loop. By tuning the
three constants in the PID controller algorithm, the control action is provided; the general PID formula is
the following:

The user has the possibility to change the loop parameters (Kp, Ki and Kd). These operations are not
allowed by CAENGECO2020 Control Software, but they can be done only in transparent mode (see SY4527
manual). By typing P from the main menu, it is possible to open the interface to modify the PID coefficients
of the channels. All changes of the coefficients are saved by typing S (see figure below):

1
EXTTRIP and INTTRIP parameters are expressed in Hexadecimal format

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Fig. 4 – PID coefficients setting

N.B. The PID coefficients can be modified when the channels are switched off. In case of change of the
coefficients with the channels on, a confirmation message asks authorization to turn off the channel and
change the coefficients.
Examples of how to set the PID Digital Regulation System, in order to adapt to load changes, are
thoroughly explained in the Application Note A251X Board Family PID Digital Regulation System, that
can be downloaded from the A251x page at www.caen.it web site.

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Tools for Discovery
n Electronic Instrumentation

CAEN SpA is acknowledged as the only company in the world providing a complete range of High/Low Voltage Power Supply
systems and Front-End/Data Acquisition modules which meet IEEE Standards for Nuclear and Particle Physics. Extensive
Research and Development capabilities have allowed CAEN SpA to play an important, long term role in this field. Our
activities have always been at the forefront of technology, thanks to years of intensive collaborations with the most
important Research Centres of the world. Our products appeal to a wide range of customers including engineers, scientists
and technical professionals who all trust them to help achieve their goals faster and more effectively.

CAEN S.p.A. CAEN GmbH CAEN Technologies, Inc.

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55049 Viareggio D-42651 Solingen - Germany Staten Island, NY 10305
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info@caen.it info@caen-de.com info@caentechnologies.com
www.caen.it www.caen-de.com www.caentechnologies.com

CAEN
Tools for Discovery
Electronic Instrumentation

A251x Series 50W LV Boards User Manual rev. 15 - 22 July 2019 00102-13-A2518-MUTX
Copyright © CAEN SpA. All rights reserved. Information in this publication supersedes all earlier versions. Specifications subject to change without notice.
A251x Series 50W LV Boards User Manual 18