Regal THOMSON TS 870 Service manual

4916 - 275th Street, Langley, BC, Canada V4W 0A3 · Telephone [phone]
Email: [email protected] · www.thomsonps.com
PM
1
75
Rev 0 23/02/10
TS 870
AUTOMATIC TRANSFER SWITCH
WITH TSC 7320 CONTROLLER
(OPEN & CLOSED TRANSITION)
INSTALLATION, OPERATING & SERVICE
MANUAL

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TABLE OF CONTENTS
1. PRODUCT REVISION HISTORY 4
2. EQUIPMENT STORAGE 4
2.1. EQUIPMENT STORAGE 4
2.2. EQUIPMENT OPERATING 5
3. NOTES TO INSTALLER 5
3.1. INSTALLATION CODES/PERMITS: 5
3.2. APPLICATION: 5
3.3. INSTALLATION LOCATION: 5
3.4. POWER CABLING: 5
3.5. CONTROL WIRING: 6
3.6. GENERATOR SET AUTOMATIC OPERATION: 6
3.7. LOAD TYPES: 6
3.8. UPSTREAM OVER CURRENT PROTECTION (NON-SERVICE ENTRANCE
RATED TS 870): 6
3.9. UPSTREAM OVERCURRENT PROTECTION (SERVICE ENTRANCE RATED
TS870): 6
3.10. WITHSTAND/INTERRUPTING CURRENT RATINGS: 7
3.11. TRANSFER SWITCHES WITH INTEGRAL OVER CURRENT PROTECTION 7
3.12. TRANSFER SWITCHES WITH MULTI-TAP VOLTAGE CAPABILITY 7
3.13. REMOTE START CONTACT FIELD WIRING 8
3.14. DIELECTRIC TESTING 8
3.15. INSTALLATION OF OPEN TYPE TRANSFER SWITCHES 8
3.16. SEISMIC ANCHORING 8
4. GENERAL DESCRIPTION 11
4.1. TSC 7320 ATS CONTROLLER 11
4.2. ATS POWER SWITCHING MECHANISM 12
4.3. PRODUCT MODEL CODE 14

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4.4. TYPICAL COMMISSIONING PROCEDURES 15
5. AUTOMATIC SEQUENCE OF OPERATION 15
5.1. STANDARD ATS - OPEN TRANSITION 15
5.2. STANDARD ATS - CLOSED TRANSITION 16
5.3. SERVICE ENTRANCE RATED ATS 20
5.4. TEST MODES 24
6. OVER CURRENT PROTECTION 26
6.1. STANDARD TS 870 AUTOMATIC TRANSFER SWITCH 26
6.2. OPTIONAL TS 870 AUTOMATIC TRANSFER SWITCH WITH INTEGRAL
OVER CURRENT PROTECTION 26
7. GENERAL NOTES ON SERVICING TRANSFER SWITCH MECHANISMS 27
8. ATS MANUAL OPERATING INSTRUCTIONS 29
8.1. TSC 7320 PUSH BUTTON CONTROLS FOR MANUAL OPERATION 29
8.2. S-STYLE ATS - MANUAL OPERATION 31
8.3. MO STYLE ATS -MANUAL OPERATION 33
9. RECOMMENDED MAINTENANCE 38
10. FRONT VIEW (TYPICAL) 3 / 4 POLE 100A-800A S-STYLE TRANSFER
MECHANISM (MECHANISM FRONT COVER REMOVED) 39
11. FRONT VIEW (TYPICAL) 3 / 4 POLE 1000A-1200A MECHANISM MOTOR
OPERATOR (MO) STYLE TRANSFER MECHANISM 40
12. CABLE TERMINAL INFORMATION 41
13. REQUIREMENTS FOR UPSTREAM CIRCUIT PROTECTIVE DEVICES 42
13.1. WITHSTAND CURRENT RATINGS (ALL MODELS WITHOUT INTEGRAL
OVERCURRENT PROTECTION OPTION) 42
13.2. INTERRUPTING CAPACITY CURRENT RATINGS (ALL MODELS WITH
INTEGRAL OVERCURRENT PROTECTION OPTION) 43
14. GROUND FAULT SITE TEST REQUIREMENTS 44
14.1. PERFORMANCE TEST 44
15. TROUBLESHOOTING 45

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16. REPLACEMENT PARTS 50
17. PRODUCT RETURN POLICY 52
18. NOTES 53
19. PERFORMANCE TEST FORM 54
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 23/02/10 Original release.
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.
Related Product Instruction Manuals
 TS 870 Quick Start Guide, PM173
 TSC 7320 Transfer Switch Controller, PM180
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.

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2.2. EQUIPMENT OPERATING
The transfer switch shall be operated in an environment with a temperature range not
exceeding +5° to +122° Fahrenheit (-15° to +50° Celsius) and a humidity range not
exceeding 5%-95% non-condensing.
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
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 12 Cable Terminal

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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.
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 motor full-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.

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3.10. WITHSTAND/INTERRUPTING CURRENT RATINGS:
Refer to electrical ratings shown in SECTION 13 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.
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 5.3.2 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 is changed from the factory 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
7320 controller connected into the circuit as serious damage will occur to the controller.
All AC fuses, DC control fuses and control circuit isolation plugs connected to the TSC
7320 must be removed if high voltage dielectric testing is performed in the transfer
switch. Failure to isolate the TSC 7320 controller for dielectric testing can result in
equipment malfunction and/or damage.
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 7320 ATS CONTROLLER
The TS 870 series transfer switches use a type TSC 7320 microprocessor based controller,
which provides all necessary control functions for fully automatic operation. The controller is
equipped with 2.3” back-lit LCD display which provides operating status and controls
For further information on the TSC 7320 Transfer Controller, refer to separate instruction manual
PM180.

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4.2. ATS POWER SWITCHING MECHANISM
There are two types of ATS power switching mechanisms 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.
Power Switching Device auxiliary contacts 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 7320 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 (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 7320 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:

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4.4. TYPICAL COMMISSIONING PROCEDURES
CAUTION
Commissioning procedures must be performed by
qualified personnel only. Ensure the Automatic
Transfer Switch (ATS) ATS Power Chassis & Voltage
Sensing Isolation Plugs PL12 & PL 15 are disconnected
prior to energizing the supply sources. Manually place
the transfer switch mechanism in the neutral position
prior to applying power. Failure to do so may result in
equipment failure or personal injury.
NOTE: The Typical Automatic Transfer Switch Commissioning Procedures Model Series TS
870, Appendix A, is provided for general information only pertaining to typical site installations
and applications. Contact Thomson Power Systems for further information as may be required.
5. AUTOMATIC SEQUENCE OF OPERATION
5.1. STANDARD ATS - OPEN TRANSITION
When utility supply voltage drops below a preset nominal value (adjustable from 50%
to 95% of nominal) on any phase, an engine start delay circuit is initiated and the
transfer to utility supply signal will be removed (i.e. contact opening). Following expiry
of the engine start delay period (adjustable from 0 to 30 sec.) an engine start signal
(contact closure) will be given.
Once the engine starts, an engine warm-up timer will be initiated. Once the warm-up
timer expires (adjustable from 0 to 60 min.), the Transfer to Generator Supply signal
(contact closure) will be given to the transfer switch mechanism. The load will then
transfer from the utility supply to the generator supply via the motor driven mechanism.
The generator will continue to supply the load until the utility supply has returned. The
retransfer sequence is completed as follows: when the utility supply voltage is restored
to above 90% of nominal voltage on all phases, a transfer return delay circuit will be
initiated. Following expiry of the Utility Return Timer (adjustable from 0 to 60 min), the
Transfer to Generator Supply signal will be removed (contact opening), then the
Transfer to Utility Supply signal (contact closure) will be given to the transfer switch
mechanism. The ATS will then retransfer the load from the generator supply back to
the utility supply.
NOTE: A neutral delay timer circuit will delay the transfer sequence in the neutral
position (i.e. both power switching devices open) until the neutral delay time period
expires.
An engine cooldown timer circuit will be initiated once the load is transferred from the
generator supply. Following expiry of the cooldown delay period (adjustable from 0 to

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60 minutes), the engine start signal will be removed (contact opening) to initiate
stopping of the generator set.
5.2. STANDARD ATS - CLOSED TRANSITION
NOTE: This section applies only to Closed Transition configured transfer switches.
For transfer switches equipped with the Closed Transition transfer option, the ATS is
configured to operate as follows:
Under normal closed transition operating conditions, the transfer switch operates
automatically during a failure and restoration of utility power and does not require
operator intervention.
When utility supply voltage drops below a preset nominal value (50 – 95% of rated
adjustable) on any phase, an engine start delay circuit will be initiated and the transfer
to utility supply signal will be removed (i.e. contact opening). Following expiry of the
engine start delay period (0 - 30 sec. adjustable) an engine start signal (contact closure)
will be given.
Once the engine starts, a warmup time delay will be initiated. Once the warmup timer
(0-60 Min adjustable) expires, the transfer to generator supply signal (contact closure)
will be given to the transfer switch mechanism. The load will then transfer from the
utility supply (i.e. opening the utility power switching device) to the generator supply
(closing the generator power switching device) via motor driven mechanism to
complete a “Break-before-make” open transition transfer sequence.
The generator will continue to supply the load until the utility supply has returned and
the retransfer sequence is completed as follows: When the utility supply voltage is
restored to above 90% of nominal voltage on all phases, a re-transfer sequence will be
initiated once the Utility Return timer expires. The utility will close its power switching
device when it is in synchronism with the generator supply utilizing the TSC 7320 in-
phase detector. The generator power switching device will immediately trip open
approximately 50-100 milliseconds after the utility power switching device closes to
complete the make-before-break re-transfer sequence.
An engine cooldown timer circuit will be initiated once the load is transferred from the
generator supply. Following expiry of the cooldown delay period (0 - 60 min.
adjustable) the engine start signal will be removed (contact opening) to initiate stopping
of the generator set.

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Closed Transition Operation Sequence Diagram
(Normal Power Failure & Return Sequence)
The following operating sequences and time delays are associated with closed
transition type transfer switches which momentarily parallel two sources of supply for
less than 100 milliseconds.
NOTE: TS870 400A to 1200A, extended parallel and soft load closed transition ATS
are implemented using the TSC900 controller. Refer to the TS870 commercial &
Industrial ATS brochure PM174 for details.
For closed transition type transfer switches, which utilize extended parallel operation
for soft-loading operating sequences, refer to the TSC900 separate instruction manual.
1. Transfer Control Switch (Open/Closed Transition): A two position selector switch is
provided on the front of the transfer switch for operator section of desired operation.
The 2 positions are as follows:
 OPEN TRANSITION: The transfer switch will operate in a “break-
before-make” open transition sequence during load transfers. A
programmed neutral delay period will occur during the transfer
sequence to ensure voltage decays on the load bus before load is
re-applied. The two sources will not be paralleled at any time during
operation in this mode.

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 CLOSED TRANSITION: When both sources of supply are available,
the transfer switch will operate in a “make-before-break” closed
transition sequence during load transfers.
NOTE: If only one source of supply is available during an initiated transfer
sequence, the control system will automatically revert to an open transition transfer
sequence.
2. Synchronizing Protection: To ensure both sources are in synchronism prior to
initiating a closed transition transfer sequence, a TSC 7320 in-phase monitor is
used. The controller has a Sync page to allow monitoring of phase and voltage of
the 2 sources. The built-in sync check relay will block a closed transition transfer
sequence until both sources phase angle and voltages are within programmed
limits. The synch check relay settings are factory programmed to the following:
Factory Settings:
Frequency Delta: ±0.5Hz
Voltage Delta: 30V PhN
Phase Angle Delta: 10°
NOTE: The standard closed transition transfer switch does not contain an
automatic synchronizer to control the generators frequency or voltage to bring it
within limits of the sync check relay. For correct closed transition transfer operation,
the system requires the generators frequency to be set within 0.25% of nominal
frequency and the generators voltage to be set within 0.5% of nominal voltage.
3. Closed Transition Time Period: The time period in which both sources of supply are
paralleled together during the closed transition transfer sequence is 50-100
milliseconds (maximum). The time period is inherently controlled by operation of
auxiliary contacts from the power switching devices (i.e. when one switching