Racal Instruments 1260 VXI User manual

1260 VXI
SWITCHING CARD
1260-121A/B
12 CHANNEL PLUG-IN
PUBLICATION NO. 980824-121
RACAL INSTRUMENTS
United States
(Corporate Headquarters and Service Center)
4 Goodyear Street, Irvine, CA 92618
Tel: [phone]; Fax: [phone]
5730 Northwest Parkway Suite 700, San Antonio, TX 78249
Tel: [phone]; Fax: [phone]
Europe
(European Headquarters and Service Center)
18 Avenue Dutartre, 78150 LeChesnay, France
Tel: [phone]; Fax: [phone]
29-31 Cobham Road, Wimborne, Dorset BH21 7PF, United Kingdom
Tel: [phone]; Fax: [phone]
Via Milazzo 25, 20092 Cinisello B, Milan, Italy
Tel: [phone]; Fax: [phone]
Technologie Park, Friedrich Ebert Strasse, 51429 Bergisch Gladbach, Germany
Tel: [phone]; Fax: [phone]
[e-mail]
[email protected]
[e-mail]
http://www.racalinstruments.com/
PUBLICATION DATE: October 29, 2003
Copyright 2001 by Racal Instruments, Inc. Printed in the United States of America. All rights reserved.
This book or parts thereof may not be reproduced in any form without written permission of the publisher.

THANK YOU FOR PURCHASING THIS RACAL INSTRUMENTS PRODUCT.
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WARRANTY STATEMENT
All Racal Instruments, Inc. products are designed and manufactured to exacting standards and in full
conformance to Racal’s ISO 9001 procedures.
This warranty does not apply to defects resulting from any modification(s) of any product or part without
Racal’s express written consent, or misuse of any product or part. The warranty also does not apply to fuses,
software, non-rechargeable batteries, damage from battery leakage, or problems arising from normal wear,
such as mechanical relay life, or failure to follow instructions.
This warranty is in lieu of all other warranties, expressed or implied, including any implied warranty of
merchantability or fitness for a particular use. The remedies provided herein are buyer’s sole and exclusive
remedies.
For the specific terms of your standard warranty, or optional extended warranty or service agreement, contact
your Racal customer service advisor. Please have the following information available to facilitate service.
1. Product serial number
2. Product model number
3. Your company and contact information
You may contact your customer service advisor by:
E-Mail: [e-mail]
Telephone: [phone] (USA)
[phone] (UK)
[phone] (Hong Kong)
Fax: [phone] (USA)
[phone] (UK)
[phone] (Hong Kong)

RETURN of PRODUCT
Authorization is required from Racal Instruments before you send us your product for service or calibration.
Call your nearest Racal Instruments support facility. A list is located on the last page of this manual. If you are
unsure where to call, contact Racal Instruments, Inc. Customer Support Department in Irvine, California, USA
at 1-800-722-3262 or 1-949-859-8999 or via fax at 1-949-859-7139. We can be reached at:
[e-mail].
PROPRIETARY NOTICE
This document and the technical data herein disclosed, are proprietary to Racal Instruments, and shall not,
without express written permission of Racal Instruments, be used, in whole or in part to solicit quotations from
a competitive source or used for manufacture by anyone other than Racal Instruments. The information herein
has been developed at private expense, and may only be used for operation and maintenance reference
purposes or for purposes of engineering evaluation and incorporation into technical specifications and other
documents which specify procurement of products from Racal Instruments.
DISCLAIMER
Buyer acknowledges and agrees that it is responsible for the operation of the goods purchased and should
ensure that they are used properly and in accordance with this handbook and any other instructions provided
by Seller. RII products are not specifically designed, manufactured or intended to be used as parts,
assemblies or components in planning, construction, maintenance or operation of a nuclear facility, or in life
support or safety critical applications in which the failure of the RII product could create a situation where
personal injury or death could occur. Should Buyer purchase RII product for such unintended application,
Buyer shall indemnify and hold RII, its officers, employees, subsidiaries, affiliates and distributors harmless
against all claims arising out of a claim for personal injury or death associated with such unintended use.

FOR YOUR SAFETY
Before undertaking any troubleshooting, maintenance or exploratory procedure, read carefully the
WARNINGS and CAUTION notices.
This equipment contains voltage hazardous to
human life and safety, and is capable of
inflicting personal injury.
If this instrument is to be powered from the AC line (mains) through an
autotransformer, ensure the common connector is connected to the neutral (earth
pole) of the power supply.
Before operating the unit, ensure the conductor (green wire) is connected to the
ground (earth) conductor of the power outlet. Do not use a two-conductor extension
cord or a three-prong/two-prong adapter. This will defeat the protective feature of the
third conductor in the power cord.
Maintenance and calibration procedures sometimes call for operation of the unit with
power applied and protective covers removed. Read the procedures and heed
warnings to avoid “live” circuit points.
Before operating this instrument:
1. Ensure the proper fuse is in place for the power source to operate.
2. Ensure all other devices connected to or in proximity to this instrument are properly grounded or
connected to the protective third-wire earth ground.
If the instrument:
- fails to operate satisfactorily
- shows visible damage
- has been stored under unfavorable conditions
- has sustained stress
Do not operate until, performance is checked by qualified personnel.

1260-121A/B User Manual
i
Table of Contents
Chapter 1...........................................................................................................................1-1
SPECIFICATIONS .......................................................................................................................1-1
Introduction ..............................................................................................................................1-1
Specifications ...........................................................................................................................1-2
Power Dissipation.....................................................................................................................1-3
About MTBF .............................................................................................................................1-4
Ordering Information ............................................................................................................... 1-5
Chapter 2...........................................................................................................................2-1
INSTALLATION INSTRUCTIONS................................................................................................2-1
Unpacking and Inspection ........................................................................................................2-1
Reshipment Instructions...........................................................................................................2-1
Installation ................................................................................................................................2-1
Module Configuration ...............................................................................................................2-1
Front Panel Connectors ........................................................................................................2-3
Mating Connectors................................................................................................................2-4
More About Maximum Current Ratings .................................................................................2-6
Installation ............................................................................................................................... 2-7
Chapter 3...........................................................................................................................3-1
MODULE OPERATION................................................................................................................3-1
Operating Modes......................................................................................................................3-1
Operating In Message-Based Mode .........................................................................................3-1
Channel Descriptors For The 1260-121 ................................................................................3-1
Reply To The MOD:LIST? Command.......................................................................................3-2
Operating in Register-Based Mode ..........................................................................................3-3
1260-121A/B Example Code.................................................................................................3-7
EMERGENCY RESET ...........................................................................................................3-10

1260-121A/B User Manual
ii
Connecting the Safety Switch .............................................................................................3-10
Normally-Open and Normally-Closed Switches ..................................................................3-10
Local and Global Reset Options .........................................................................................3-12
Momentary vs. Latching Switches.......................................................................................3-13
Chapter 4...........................................................................................................................4-1
OPTIONAL HARNESS ASSEMBLIES .........................................................................................4-1
Chapter 5...........................................................................................................................5-1
PRODUCT SUPPORT.................................................................................................................5-1
Product Support .......................................................................................................................5-1
Reshipment Instructions...........................................................................................................5-1
Support Offices ........................................................................................................................5-2
Repair and Calibration Request Form ......................................................................................5-3

1260-121A/B User Manual
iii
List of Figures
Figure 1-1, The 1260-121A/B...................................................................................................... 1-1
Figure 2-2, Front Panel Connector Pin Numbering ..................................................................... 2-3
Figure 3-1, JP6 Configuration Jumper ...................................................................................... 3-11
Figure 3-2, JP7 Configuration Jumper ...................................................................................... 3-12
List of Tables
Table 2-1, 1260-121A/B Front-Panel Connections...................................................................... 2-4
Table 3-1, Register Offset Addresses of the 1260-121A/B Module ............................................. 3-4
Table 3-2, ID Register Functionality of the 1260-121A/B Module ................................................ 3-4
Table 3-3, Port A Register Functionality of the 1260-121A/B Module.......................................... 3-5
Table 3-4, Port B Register Functionality of the 1260-121A/B Module.......................................... 3-5
Table 3-5, EPROM Descriptor Functionality of the 1260-121A/B Module.................................... 3-6

1260-121A/B User Manual
iv
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1260-121A/B User Manual
Racal Instruments Ó2003 Specifications 1-1
Chapter 1
SPECIFICATIONS
Introduction The 1260-121A/B is a plug-in switch module developed for the
Racal Instruments 1260-100 Adapt-a-Switch Carrier. The
1260-121A/B includes the following features:
· Standard Adapt-a-Switch plug-in design, providing for ease of
replacement
· Data-Driven embedded descriptor, allowing immediate use with
any Option-01T switch controller, regardless of firmware
revision level.
Figure 1-1, The 1260-121A/B

1260-121A/B User Manual
Specifications 1-2 Racal Instruments Ó2003
The 1260-121A/B is a 12-channel single-wire switch consisting of
12 individual SPDT relay switches. The version “A” has a screw
terminal block interface and version “B” has Rack-and-Panel
connectors. The 1260-121A/B plug-in fits into a 1260-100 Adapt-a-
Switch Carrier.
Specifications Bandwidth (-3dB) Small signal: 35MHz
Power: 400Hz
Insertion Loss
1 KHz < -1dB
Isolation
1 KHz > 100dB
Crosstalk
1 KHz < -100dB
Switching Voltage
AC 250V, Max
DC 125V, Max
Switching Current
AC 12A, Max. (1260-121A)
13A, Max. (1260-121B)
DC 10A, Max
Switching Power
AC 1250VA, Max
DC 150W, Max
Path resistance < 0.5W(measured by voltage drop,
6VDC, 1A)
Thermal EMF < 20uV
Capacitance
Channel-Chassis < 1pF
Open-Channel < 12pF
Insulation resistance > 109W
Relay Settling Time < 10ms
Shock 30g, 11ms, ½ sine wave
Vibration 0.013in. P-P, 5-55Hz
Bench Handling 4 in., 45°
(see the Mating
Connectors
section in
Chapter 2)

1260-121A/B User Manual
Racal Instruments Ó2003 Specifications 1-3
Cooling See 1260-100 cooling data
Temperature
Operating 0°C to +60°C
Non-operating -40°C to +75°C
Relative Humidity 85% Max., non-condensing at
< 30°C
Altitude
Operating 10,000 feet
Non-operating 15,000 feet
Power Requirements
+5VDC 0.9A Max.
Weight 13oz. (0.45kg)
MTBF 979,058 hours (MIL-HDBK-217E)
Power
Dissipation
While the cooling of the Adapt-a-Switch carrier is dependent upon
the chassis into which it is installed, the carrier can normally
dissipate approximately 100 W. Care must be taken, then, in the
selection and loading of the plug-in modules used in the carrier. It
is not possible to fully load the carrier, energize every relay, and
run full power through every set of contacts, all at the same time.
In practice this situation would never occur.
To properly evaluate the power dissipation of the plug-in modules,
examine the path resistance, the current passing through the relay
contacts, the ambient temperature, and the number of relays
closed at any one time.
For example, if a 1260-118 module (containing 80 relays) has 25
relays closed, passing a current of 0.5 A, then:
Total power dissipation =
[(current)2* (path resistance) * 25 ] + (quiescent power)
By substituting the actual values:
Total power dissipation =
[(0.5 A)2* (1 W) * 25] + ( 0.75 W) = 7 W at 55°C
This is acceptable power dissipation for an individual plug-in
module. If five additional modules are likewise loaded, then the
overall carrier dissipation is approximately 36 W, which is well
within the cooling available in any commercial VXIbus chassis. In
practice, rarely are more than 25% of the module’s relays

1260-121A/B User Manual
Specifications 1-4 Racal Instruments Ó2003
energized simultaneously, and rarely is full rated current run
through every path. In addition, the actual contact resistance is
typically one-half to one-fourth the specified maximum, and
temperatures are normally not at the rated maximum. The power
dissipated by each plug-in should be no more than 15 W if all six
slots are used simultaneously. This yields the following guideline:
0.5 A Max. 56 relays closed
1.0 A Max. 14 relays closed
2.0 A Max. 4 relays closed
Most users of a signal-type switch, such as the 1260-118, switch
no more than a few hundred milliamperes and are able to energize
all relays simultaneously, should they so desire. The numbers in
the above table represent worst-case, elevated-temperature, end-
of-life conditions.
Additionally, if fewer plug-in modules are used, more power may
be dissipated by the remaining cards. By using a chassis with high
cooling capacity, such as the Racal Instruments 1261B, almost
any configuration may be realized.
About MTBF The 1260-121A/B MTBF is 979,058 hours, calculated in
accordance with MIL-HDBK-217E, with the exception of the
electromechanical relays. Relays are excluded from this
calculation because relay life is strongly dependent upon operating
conditions. Factors affecting relay life expectancy are:
1. Switched voltage
2. Switched current
3. Switched power
4. Maximum switching capacity
5. Maximum rated carrying current
6. Load type (resistive, inductive, capacitive)
7. Switching repetition rate
8. Ambient temperature
The most important factor is the maximum switching capacity,
which is an interrelationship of maximum switching power,
maximum switching voltage and maximum switching current.
When a relay operates at a lower percentage of its maximum
switching capacity, its life expectancy is longer. The maximum
switching capacity specification is based on a resistive load, and

1260-121A/B User Manual
Racal Instruments Ó2003 Specifications 1-5
must be further de-rated for inductive and capacitive loads.
For more details about the above life expectancy factors, refer to
the data sheet for the switch plug-in module.
The relay used on the 1260-121A/B plug-in is Racal part no.
310265-001. The relay manufacturer’s specifications for this relay
are:
Life Expectancy
Mechanical 10,000,000 operations
Electrical 100,000 operations at full rated load
For additional relay specifications, refer to the relay manufacturer’s
data sheet.
Ordering
Information
Listed below are part numbers for both the 1260-121A and
1260-121B switch modules and available mating connector
accessories. Each 1260-121B uses two mating connectors.
ITEM DESCRIPTION PART #
1260-121A Switch Module 1260-121A w/ Termination Block Interface
Consists of:
PCB Assembly
Manual for 1260-121A/B
407740-001
405167-001
980824-121
1260-121B Switch
Module
1260-121B, 12 Channel SPDT, 10 A
Consists of:
PCB Assembly
Shipping Kit (mating connectors, manual)
407740-002
405167-002
407653-121B
20 Pin Mating Connector
“B” Model Only
20 Pin Conn. Kit w/backshell & solder cup pins 407660
Cable Assy. 6ft, Sleeved
“B” Model Only
18-Conductor Cable Assy, 6 Ft, 14 AWG (2 Req’d) 407657-018
Additional Manual Manual for 1260-121A/B 980824-121

1260-121A/B User Manual
Specifications 1-6 Racal Instruments Ó2003
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1260-121A/B User Manual
Racal Instruments Ó2003 Installation Instructions 2-1
Chapter 2
INSTALLATION INSTRUCTIONS
Unpacking and
Inspection
1. Before unpacking the switching module, check the exterior of
the shipping carton for any signs of damage. All irregularities
should be noted on the shipping bill and reported.
2. Remove the instrument from its carton, preserving the factory
packaging as much as possible.
3. Inspect the switching module for any defects or damage.
Immediately notify the carrier if any damage is apparent.
4. Have a qualified person check the instrument for safety before
use.
Reshipment
Instructions
1. Use the original packing material when returning the switching
module to Racal Instruments for servicing. The original
shipping carton and the instrument’s plastic foam will provide
the necessary support for safe reshipment.
2. If the original packing material is unavailable, wrap the
switching module in an ESD Shielding bag and use plastic
spray foam to surround and protect the instrument.
3. Reship in either the original or a new shipping carton.
Installation Installation of the 1260-121A/B Switching Module into a 1260-100
Carrier assembly is described in the Installation section of the
1260-100 Adapt-a-Switch Carrier Manual.
Module
Configuration
The 1260-121A/B is a 12-channel single-wire switch module
consisting of twelve SPDT relay switches. This architecture
permits the 1260-121A/B module to be organized via software in
any configuration from twelve SPDT to one 12PDT, or any
combination in between, by use of the Include command, without
the use of hardware jumpers. This is the same as a 1-wire, 2-wire,

1260-121A/B User Manual
Installation Instructions 2-2 Racal Instruments Ó2003
…, n-wire switch.
In addition, by jumpering pins at the module connectors, the user
can configure the module as a SP2T, SP3T, etc., up to a SP12T
switch. This type of configuration is known as a multiplexer.
For a block diagram of the 1260-121A/B, see Figure 2-1.
Figure 2-1, 1260-121A/B Block Diagram
CHAN, 0
CHAN, 1
CHAN, 2
CHAN, 11

1260-121A/B User Manual
Racal Instruments Ó2003 Installation Instructions 2-3
Front Panel
Connectors
The 1260-121A/B has two 20-pin front-panel connectors, labeled
J200 and J202. It has one pin for each input and one for each
output. See Figure 2-2 for pin numbering. Table 2-1 shows the
mapping of channel numbers to connector pins. Information about
available mating connectors is provided immediately after
Table 2-1.
Figure 2-2, Front Panel Connector Pin Numbering

1260-121A/B User Manual
Installation Instructions 2-4 Racal Instruments Ó2003
Table 2-1, 1260-121A/B Front-Panel Connections
Channel Connector Pin Relay
0 In J200 A 1
0 Out N.O. J200 B 1
0 Out N.C. J200 C 1
1 In J200 D 2
1 Out N.O. J200 E 2
1 Out N.C. J200 F 2
2 In J200 H 3
2 Out N.O. J200 J 3
2 Out N.C. J200 K 3
3 In J200 L 4
3 Out N.O. J200 M 4
3 Out N.C. J200 N 4
4 In J200 P 5
4 Out N.O. J200 R 5
4 Out N.C. J200 S 5
5 In J200 T 6
5 Out N.O. J200 U 6
5 Out N.C. J200 V 6
6 In J201 A 7
6 Out N.O. J201 B 7
6 Out N.C. J201 C 7
7 In J201 D 8
7 Out N.O. J201 E 8
7 Out N.C. J201 F 8
8 In J201 H 9
8 Out N.O. J201 J 9
8 Out N.C. J201 K 9
9 In J201 L 10
9 Out N.O. J201 M 10
9 Out N.C. J201 N 10
10 In J201 P 11
10 Out N.O. J201 R 11
10 Out N.C. J201 S 11
11 In J201 T 12
11 Out N.O. J201 U 12
11 Out N.C. J201 V 12
Mating
Connectors
Mating connector accessories are available for the 1260-121B:
20 Pin Connector Kit with backshell and pins
P/N 407660
20 Pin, 18 Conductor Cable Assembly, 6 Ft., 14 AWG
P/N 407657-018