THOMSON TS 870 Service manual

PM062
Rev 11
16/04/19
TS 870
AUTOMATIC TRANSFER SWITCH
WITH TSC 900 CONTROLLER
(OPEN & CLOSED TRANSITION)
INSTALLATION, OPERATING & SERVICE
MANUAL
Part #006332
9087A - 198th Street, Langley, BC, Canada V1M 3B1 ·Telephone [phone]
Email: [e-mail] ·
www.thomsonps.com

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TABLE OF CONTENTS
1. PRODUCT REVISION HISTORY 4
2. EQUIPMENT STORAGE 5
2.1. EQUIPMENT STORAGE 5
3. NOTES TO INSTALLER 5
3.1. INSTALLATION CODES/PERMITS: 6
3.2. APPLICATION: 6
3.3. INSTALLATION LOCATION: 6
3.4. POWER CABLING: 6
3.5. CONTROL WIRING: 6
3.6. GENERATOR SET AUTOMATIC OPERATION: 7
3.7. LOAD TYPES: 7
3.8. UPSTREAM OVER CURRENT PROTECTION
(NON-SERVICE ENTRANCE RATED TS 870): 7
3.9. UPSTREAM OVERCURRENT PROTECTION
(SERVICE ENTRANCE RATED TS870): 7
3.10. WITHSTAND/INTERRUPTING CURRENT RATINGS: 7
3.11. TRANSFER SWITCHES WITH INTEGRAL OVER CURRENT PROTECTION 8
3.12. TRANSFER SWITCHES WITH MULTI-TAP VOLTAGE CAPABILITY 8
3.13. REMOTE START CONTACT FIELD WIRING 9
3.14. DIELECTRIC TESTING 9
3.15. INSTALLATION OF OPEN TYPE TRANSFER SWITCHES 9
3.16. SEISMIC ANCHORING 9

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4. GENERAL DESCRIPTION 13
4.1. TSC 900 ATS CONTROLLER 13
4.2. ATS POWER SWITCHING MECHANISM 14
4.3. PRODUCT MODEL CODE 18
4.4. TYPICAL COMMISSIONING PROCEDURES 19
5. AUTOMATIC SEQUENCE OF OPERATION 19
5.1. STANDARD ATS - OPEN TRANSITION 19
5.2. STANDARD ATS - CLOSED TRANSITION 20
5.3. DUAL SOURCE ATS 23
5.4. SERVICE ENTRANCE RATED ATS 25
5.5. TEST MODES 30
6. OVER CURRENT PROTECTION 31
6.1. STANDARD TS 870 AUTOMATIC TRANSFER SWITCH 31
6.2. OPTIONAL TS 870 AUTOMATIC TRANSFER SWITCH WITH INTEGRAL OVER
CURRENT PROTECTION 31
7. GENERAL NOTES ON SERVICING TRANSFER SWITCH MECHANISMS 33
8. ATS MANUAL OPERATING INSTRUCTIONS 35
8.1. S-STYLE ATS -MANUAL OPERATION 35
8.2. T-STYLE ATS -MANUAL OPERATION 37
8.3. MO STYLE ATS -MANUAL OPERATION 39
9. FRONT VIEW (TYPICAL) 3 / 4 POLE 100A-250A S-STYLE TRANSFER
MECHANISM 47
10. FRONT VIEW (TYPICAL) 3 POLE 400A-800A S-STYLE TRANSFER MECHANISM
(MECHANISM FRONT COVER REMOVED) 48
11. FRONT VIEW (TYPICAL) 3 / 4 POLE MOTOR OPERATOR (MO) STYLE TRANSFER
MECHANISM (400A-800A CLOSED TRANSITION, 1000-1200A) 49
12. CABLE TERMINAL INFORMATION 50

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13. REQUIREMENTS FOR UPSTREAM CIRCUIT PROTECTIVE DEVICES 51
13.1. WITHSTAND CURRENT RATINGS (ALL MODELS WITHOUT INTEGRAL
OVERCURRENT PROTECTION OPTION) 51
13.2. INTERRUPTING CAPACITY CURRENT RATINGS (ALL MODELS WITH INTEGRAL
OVERCURRENT PROTECTION OPTION) 52
14. GROUND FAULT SITE TEST REQUIREMENTS 52
14.1. PERFORMANCE TEST 52
15. TROUBLESHOOTING 53
16. REPLACEMENT PARTS 58
17. PRODUCT RETURN POLICY 60
18. NOTES 61
19. PERFORMANCE TEST FORM 62
APPENDIX A – TYPICAL TS 870 ATS COMMISSIONING PROCEDURE
APPENDIX B – TS 870 SYSTEM VOLTAGE CHANGE PROCEDURE
APPENDIX C –SEISMIC CERTIFICATE

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1. PRODUCT REVISION HISTORY
The following information provides an historical summary of changes made to this product since the
original release.
Operating & Service Manual Version
Rev 0 04/11/19 Original release.
Rev 1 05/03/08 Changes to incorporate reversing style ATS Motor for 100-250A
transfer switches.
Rev 2 05/05/26 Revisions to Section 8 and Section 18.
Rev 3 06/05/08 Revisions to Section 15.
Rev 4 07/07/31 Changes to Incorporate new S-Style 400A mechanism
Rev 5 08/03/05 Changes to Incorporate new S-Style mechanism (100A, 150A, 200A,
250A, 600A, 800A)
Rev 6 08/08/01 Changes to Incorporate optional TSC 80e Transfer Controller
Rev 7 09/01/01 Changes to Incorporate standard TSC 80e Transfer Controller
Rev 8 10/01/25
Changes to Incorporate Seismic Certification and Mounting
Requirements
Rev 9 14/01/08 Update to Marathon Thomson Power System Logo
Rev 10 15/04/07 Changes to incorporate TSC 900 Transfer Switch Controller
Rev 11 16/04/19 Added Closed Transition Transfer models, and Motor Operator Style
ATS mechanisms
Contact Thomson Power Systems, to obtain applicable instruction manuals or if in doubt about
any matter relating to installation, operation or maintenance. Soft copy of the most current
version is available at www.thomsonps.com.
NOTE: All information contained in this manual is for reference only and is subject to change
without notice.

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Related Product Instruction Manuals
•TS 870 Quick Start Instruction Manual, PM150
•TSC 900 Transfer Switch Controller, PM151
•TSC 900 ModbusTM Communication, PM152
Contact Thomson Power Systems, to obtain these instruction manuals. Soft copy of the most
current versions of these manuals are available at www.thomsonps.com.
2. EQUIPMENT STORAGE
The following procedures are required for correct storage of the transfer switch prior to installation.
CAUTION
Failure to store and operate equipment under the specified environmental conditions
may cause equipment damage and void warranty.
2.1. EQUIPMENT STORAGE
The transfer switch shall be stored in an environment with a temperature range not
exceeding -4° to +158° Fahrenheit (-20° to +70° Celsius) and a humidity range not
exceeding 5%-95% non-condensing. Before storing, unpack sufficiently to check for
concealed damage. If concealed damage is found, notify the ATS supplier and the
Carrier immediately. Repack with the original, or equivalent packing materials. Protect
from physical damage. Do not stack. Store indoors in a clean, dry, well ventilated area
free of corrosive agents including fumes, salt and concrete/cement dust. Apply heat as
necessary to prevent condensation.
3. NOTES TO INSTALLER
DANGER
Arc Flash and Shock Hazard. Will cause severe injury or death.
Do not open equipment until ALL power sources are disconnected
This equipment must be installed and serviced only by qualified electrical
personnel utilizing safe work practices and appropriate Personal Protective
Equipment (PPE). Failure to do so may cause personal injury or death

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3.1. INSTALLATION CODES/PERMITS:
Suitable permits are required by local authorities having jurisdiction prior to installing standby
generator sets and automatic transfer switches.
3.2. APPLICATION:
The TS 870 Transfer Switch is Listed by Underwriters Laboratories (UL) to Safety Standard
UL 1008 for Transfer Switches for Emergency Standby applications. This product is intended
for installation and operation on legally required standby applications for emergency power
systems as defined by the National Electrical Code (NEC).
3.3. INSTALLATION LOCATION:
The standard TS 870 transfer switch is designed for indoor wall mounting or outdoor wall
mounting with NEMA 3R rating. The transfer switch must be installed in an environment where
the temperature range is within +5° to +122° Fahrenheit (-15° to +50° Celsius) and humidity
range not exceeding 5%-95% non-condensing.
NOTE: The transfer switch must not be installed in a location where it is subjected to direct
sunlight on the front of the transfer switch door. In these applications, an optionally available
sun-shade kit must be installed.
3.4. POWER CABLING:
All power cabling entering/exiting the enclosure must be installed in suitably sized conduit per
NEC/CEC requirements. Ampacity, type and voltage rating of current carrying conductors must
also comply with NEC/CEC requirements and local authorities having jurisdiction. To ensure
satisfactory installation of this equipment, refer to manual SECTION 15 Cable Terminal
Information regarding power cable connection tightness requirements. All mechanical and
electrical connections must be checked for tightness prior to placing this equipment in service
to ensure proper operation and to validate applicable warranty coverage.
3.5. CONTROL WIRING:
All control wiring for engine start, load shed, alarm and remote test must be installed in
separate conduits from all power cabling and must utilize suitably sized conduits per NEC/CEC
requirements. All control wiring shall be sized for minimum #18 AWG. Control wiring type and
voltage rating must also comply with NEC/CEC requirements and local authorities having
jurisdiction.
NOTE: All field wiring/communication cabling that may be field installed directly onto any ATS
door mounted components must be suitably routed and protected across the door hinge to
prevent possible mechanical damage upon door opening and/or door closing.

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3.6. GENERATOR SET AUTOMATIC OPERATION:
The TS 870 transfer switch operates in conjunction with any generator set with remote
automatic starting capabilities utilizing a 2 wire, remote start control contact input. A dry
contact is provided for remote generator starting control (contact closes to start generator and
opens to stop generator).
3.7. LOAD TYPES:
The standard TS 870 is suitable for control of motors, electric discharge lamps, tungsten
filament lamps, and electric heating equipment where the sum of motorfull-load ampere ratings
and the ampere ratings of other loads do not exceed the ampere rating of the switch and the
tungsten load does not exceed 30 percent of the switch rating.
3.8. UPSTREAM OVER CURRENT PROTECTION (NON-SERVICE ENTRANCE RATED
TS 870):
Non-Service Entrance Rated TS 870 transfer switch models do not contain any integral over
current protection and require upstream over current protection devices for both Utility and
Generator sources.
3.9. UPSTREAM OVERCURRENT PROTECTION (SERVICE ENTRANCE RATED
TS870):
Service Entrance rated TS 870 transfer switch models contain integral over current protection
for the Utility source as standard. Service Entrance rated TS 870 transfer switches do not
contain any integral over current protection for the generator source and requires upstream
generator source over current protection. The Service Entrance rated TS 870 is rated for 80%
maximum continuous loading of load types as described per SECTION 3.7.
3.10. WITHSTAND/INTERRUPTING CURRENT RATINGS:
Refer to electrical ratings shown in SECTION 16 for withstand/Interrupting current ratings.
Short circuit currents listed for Standard type ATS are Withstand ratings. Short circuit currents
listed for Service Entrance type ATS are Interrupting ratings based on the ratings of the
supplied utility service disconnect circuit breaker utilized.

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3.11. TRANSFER SWITCHES WITH INTEGRAL OVER CURRENT PROTECTION
For models of transfer switch with integral over current protection, the over current protection
must be set prior to operation. The equipment will be shipped from the factory with a long-time
current setting of 100% (of the equipment rating) and maximum short-time/instantaneous
current and time delay settings.
WARNING
Do Not Energize this equipment until
device settings have been verified to
ensure proper system protection &
coordination. Failure to do so may
result in equipment failure.
Refer to SECTION 5.2.2 of this manual for additional information on operation of the Transfer
switch following an over current trip condition. Refer to information supplied with the transfer
switch documentation package for adjustment procedures on the power switching units over
current protection trip unit. Contact the factory if any additional information is required.
3.12. TRANSFER SWITCHES WITH MULTI-TAP VOLTAGE CAPABILITY
If the transfer switch has programmable multi-tap voltage capability (i.e. ATS Model Code with
Voltage Code “Y”), confirm the transfer switch has been configured for the correct system
voltage prior to installation.
WARNING
Failure to confirm and match transfer
switch voltage with the system voltage
could cause serious equipment damage.
The voltage selections and connections are shown on the drawings supplied with each transfer
switch. The factory default settings will be indicated on the calibration label attached on the
inside of the enclosure door (supplied loose on open style models). A blank label is included
to record the applicable settings if the configuration ischanged from thefactory default settings.
To change the transfer switch voltage, refer to TS 870 System Voltage Change Procedure,
Appendix B. Contact Thomson Power Systems for further information as may be required.

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3.13. REMOTE START CONTACT FIELD WIRING
As a minimum, the remote engine start control field wiring shall conform to the local
regulatory authority on electrical installations. Field wiring of a remote start contact
from a transfer switch to a control panel should conform to the following guidelines to
avoid possible controller malfunction and/or damage.
3.5.1. Minimum #14 AWG (2.5mm2) wire size shall be used for distances up to 100ft
(30m)1). For distances exceeding 100 ft. (30m) consult Thomson Power
Systems
3.5.2. Remote start contact wires should be run in a separate conduit.
3.5.3. Avoid wiring near AC power cables to prevent pick-up of induced voltages.
3.5.4. An interposing relay may be required if field-wiring distance is excessively long
(i.e. greater than 100 feet (30m)) and/or if a remote contact has a resistance of
greater than 5.0 ohms.
3.5.5. The remote start contact must be voltage free (i.e. dry contact). The use of a
powered contact will damage the transfer controller.
3.14. DIELECTRIC TESTING
Do not perform any high voltage dielectric testing on the transfer switch with the TSC
900 controller connected into the circuit as serious damage will occur to the controller.
All AC control fuses and control circuit isolation plugs connected to the TSC 900 must
be removed if high voltage dielectric testing is performed on the transfer switch.
3.15. INSTALLATION OF OPEN TYPE TRANSFER SWITCHES
Please refer to the factory for additional information.
3.16. SEISMIC ANCHORING
Model TS870 Automatic Transfer Switches and Automatic Transfer and Bypass
Isolation Switches in "standard" enclosures are seismic certified under AC156 building
code for non-structural components.
Standard enclosures are all transfer switch enclosures Thomson Power Systems offers
in NEMA 1, NEMA 2, NEMA 3R and NEMA 4X for the above listed product.
The transfer switch must be installed per the anchoring details provided for seismic
qualification. The equipment can be mounted in alternate means and still qualify if a
qualified Civil Engineer designs the alternate method of anchoring.

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Anchoring Notes:
1. Anchoring must be designed according to IBC 2012 or latest version.
2. The anchoring details shown are recommended according to the seismic
certification; design Engineer may use alternate anchors within the scope of IBC.
3. Wall anchors in concrete; use a typical concrete anchor as necessary.
4. Expansion anchors as shown. To be installed according to manufacturer's
recommendation.
5. The 800-1200A NEMA 3R ATS enclosure may be floor/wall mounted or it may be
free standing (floor mounted only); If free standing it must be a minimum of 12"
(305mm) away from pipes, conduits or other obstructions to allow for sway during a
seismic event.

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4. GENERAL DESCRIPTION
Thomson Power Systems TS 870 series of Automatic Transfer Switches employ two mechanically
interlocked enclosed contact power switching units and a microprocessor based controller to
automatically transfer system load to a generator supply in the event of a utility supply failure. System
load is then automatically re-transferred back to the utility supply following restoration of the utility
power source to within normal operating limits.
The standard TS 870 series Automatic Transfer Switch is rated for 100% system load and requires
upstream over current protection. The TS 870 Automatic Transfer Switch may be supplied with
optional integral over current protection within the enclosed contact power switching units for
applications such as Service Entrance Rated equipment. Refer to SECTION 6 of this manual for
detailed information on current protection.
4.1. TSC 900 ATS CONTROLLER
The TS 870 series transfer switches use a type TSC 900 microprocessor based controller,
which provides all necessary control functions for fully automatic operation. The TSC 900
controller consists of two parts; a front door mounted graphical touch screen display (GHC),
and a switch control unit (SCU) which is mounted inside the transfer switch door. The two parts
are interconnected via a USB 3.0 high speed communication cable which includes DC power.
USB 3.0 Cable
GHC
SCU

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For further information on the TSC 900 Transfer Controller, refer to separate instruction manual
PM151.
4.2. ATS POWER SWITCHING MECHANISM
Four types of ATS power switching mechanisms are provided with TS 870 Series ATS based
on amperage size and optional features supplied with the ATS as described below.
4.2.1. “S”- STYLE ATS MECHANISM (100A-800A, OPEN TRANSITION)
The ATS mechanism consists of 2 power
switching devices which are mounted in a
horizontal (i.e. side-by-side) configuration. The
ATS mechanism provides a positive
mechanical interlock to prevent both power
switching units from being closed at the same
time. The ATS mechanism utilizes a single
120VAC reversible gear motor drive which is
mounted in between the two power switching
devices. The transfer switch gear motor utilizes
the power from the source to which the
electrical load is being transferred. The gear
motor drives a common drive hub assembly
which in-turn operates the power switching
device toggles via independent operating arms.
Two limit switches are utilized to disconnect
control power to the gear motor once correct
operating positions are reached.
On 100-250A transfer mechanisms, the load-side of the power switching devices are
interconnected via power cable. On 400-800A transfer mechanisms, the load-side of the power
switching devices are interconnected via bus bars. The TSC 900 transfer controller provides a
standard neutral position delay timer to allow adequate voltage decay during transfer operation
to prevent out of phase transfers

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4.2.1. “T”- STYLE ATS MECHANISM (1000A-1200A, OPEN TRANSITION)
The ATS mechanism consists of 2 power
switching devices which are mounted in a
vertical stacked configuration. The ATS
mechanism provides a positive mechanical
interlock to prevent both power switching units
from being closed at the same time The ATS
mechanism utilizes a single 120VAC reversible
gear motor drive which is mounted in between
the two power switching devices. The transfer
switch gear motor utilizes the power from the
source to which the electrical load is being
transferred. The gear motor drives a common
drive hub assembly which in-turn operates the
power switching device toggles via independent
operating arms. Two limit switches are utilized
to disconnect control power to the gear motor
once correct operating positions are reached.
The TSC 900 transfer controller provides a
standard neutral position delay timer to allow
adequate voltage decay during transfer
operation to prevent out of phase transfers.

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4.2.2. MO- STYLE ATS MECHANISM (400A-800A CLOSED TRANSITION)
The ATS mechanism consists of 2 power
switching devices which are mounted in a vertical
stacked configuration. Each power switching
device uses a 120VAC motor operator with
individual spring charging mechanism and shunt
trip/close coils. The transfer switch mechanism
utilizes the power from the source to which the
electrical load is being transferred to.
The Closed Transition transfer feature allows a
make-before-break transfer sequence when both
sources of power are available. For Closed
Transition operation, the TSC 900 transfer
controller provides in-phase closing protection to
ensure all transfers are in synchronism prior to
closing.

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4.2.3. MO- STYLE ATS MECHANISM (1000A-1200A OPEN & CLOSED
TRANSITION)
The ATS mechanism consists of 2 power
switching devices which are mounted in a vertical
stacked configuration. Each power switching
device uses a 120VAC motor operator with
individual spring charging mechanism and shunt
trip/close coils. The transfer switch mechanism
utilizes the power from the source to which the
electrical load is being transferred to. Open
Transition type transfer switches are equipped
with a cable interlock mechanism to prevent both
power switching devices being closed at the
same time.
Closed Transition type transfer switches allow a
make-before-break transfer sequence when both
sources of power are available. For Closed
Transition operation, the TSC 900 transfer
controller provides in-phase closing protection to
ensure all transfers are in synchronism prior to
closing.

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4.3. PRODUCT MODEL CODE
The type of TS 870 series transfer switch supplied is identified by way of a 21digit product code
which appears on the equipment rating plate, or model, on the door of the transfer switch, and
on the transfer switch drawings. The model code structure and definitions are as follows: