Thomson-Technology TS 870 User Manual

TS 870

AUTOMATIC TRANSFER SWITCHES

With TSC 80e Controller

INSTALLATION, OPERATING &

SERVICE MANUAL

PM062 Rev 8 10/01/25

9087A – 198th Street, Langley, BC Canada V1M 3B1 Ÿ Telephone [phone]

Telefax [phone] Ÿ E-Mail: [e-mail] Ÿ www.thomsontechnology.com

TS 870 TRANSFER SWITCH

TABLE OF CONTENTS

1. PRODUCT REVISION HISTORY 1

2. EQUIPMENT STORAGE 1

2.1. ENVIRONMENTAL CONDITIONS 1

3. NOTES TO INSTALLER 2

3.1. UPSTREAM CIRCUIT PROTECTIVE DEVICES/ELECTRICAL CONNECTIONS 2

3.2. TRANSFER SWITCHES WITH INTEGRAL OVER CURRENT PROTECTION 3

3.3. TRANSFER SWITCHES WITH MULTI-TAP VOLTAGE CAPABILITY 3

3.4. SYSTEM PHASING-HIGH LEG DELTA SYSTEMS 4

3.5. REMOTE START CONTACT FIELD WIRING 5

3.6. DIELECTRIC TESTING 5

3.7. INSTALLATION OF OPEN TYPE TRANSFER SWITCHES 5

3.8. MOUNTING OF ENCLOSED TRANSFER SWITCHES 6

4. GENERAL DESCRIPTION 8

4.1. PRODUCT MODEL CODE 10

4.2. TYPICAL COMMISSIONING PROCEDURES 11

5. GENERAL THEORY OF OPERATION 11

5.1. STANDARD AUTOMATIC TRANSFER SWITCH 11

5.2. SERVICE ENTRANCE AUTOMATIC TRANSFER SWITCH 12

5.3. TEST MODES 16

6. OVER CURRENT PROTECTION 16

6.1. STANDARD TS 870 AUTOMATIC TRANSFER SWITCH 16

6.2. OPTIONAL TS 870 AUTOMATIC TRANSFER SWITCH WITH INTEGRAL OVER
CURRENT PROTECTION 16

7. GENERAL NOTES ON SERVICING TRANSFER SWITCH MECHANISM 18

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8. TRANSFER SWITCH MECHANISM – 100A-800A, S STYLE 20

8.1. MANUAL OPERATION 20

9. TRANSFER SWITCH MECHANISM –1000A-1200A, T-STYLE 22

9.1. MANUAL OPERATION 22

10. RECOMMENDED MAINTENANCE 24

11. FRONT VIEW (TYPICAL) 3 / 4 POLE 100A-250A S-STYLE TRANSFER
MECHANISM 26

12. FRONT VIEW (TYPICAL) 3 POLE 400A-800A S-STYLE TRANSFER MECHANISM
(MECHANISM FRONT COVER REMOVED) 27

13. FRONT VIEW (TYPICAL) 3 / 4 POLE 1000A-1200A T-STYLE TRANSFER
MECHANISM 28

14. CONNECTION CONFIGURATION OPTIONS 29

15. CABLE TERMINAL INFORMATION 30

16. REQUIREMENTS FOR UPSTREAM CIRCUIT PROTECTIVE DEVICES 30

16.1. WITHSTAND CURRENT RATINGS (ALL MODELS WITHOUT INTEGRAL

OVERCURRENT PROTECTION OPTION) 30

16.2. INTERRUPTING CAPACITY CURRENT RATINGS (ALL MODELS WITH INTEGRAL

OVERCURRENT PROTECTION OPTION) 31

17. GROUND FAULT SITE TEST REQUIREMENTS 31

17.1. PERFORMANCE TEST 31

18. TROUBLESHOOTING 33

19. REPLACEMENT PARTS 36

20. PRODUCT RETURN POLICY 37

21. NOTES 38

22. PERFORMANCE TEST FORM 39

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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
Rev 1 05/03/08

Rev 2 05/05/26
Rev 3 06/05/08
Rev 4 07/07/31
Rev 5 08/03/05

Rev 6 08/08/01
Rev 7 09/01/01
Rev 8 10/01/25

Original release.
Changes to incorporate reversing style ATS Motor for 100-250A

transfer switches.
Revisions to Section 8 and Section 18.
Revisions to Section 15.
Changes to Incorporate new S-Style 400A mechanism
Changes to Incorporate new S-Style mechanism (100A, 150A,

200A, 250A, 600A, 800A)
Changes to Incorporate optional TSC 80E Transfer Controller
Changes to Incorporate standard TSC 80E Transfer Controller
Changes to Incorporate Seismic Certification and Mounting

Requirements

Contact Thomson Technology, 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.thomsontechnology.com.

NOTE: All information contained in this manual is for reference only and is subject

to change without notice.

2. EQUIPMENT STORAGE

The following procedures are required for correct storage of the transfer switch prior to installation.

2.1. ENVIRONMENTAL CONDITIONS

CAUTION!!!

Failure to store and operate equipment under the specified environmental conditions may
cause equipment damage and void warranty.

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2.1.1. 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.

2.1.2. 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

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. UPSTREAM CIRCUIT PROTECTIVE DEVICES/ELECTRICAL
CONNECTIONS

To ensure satisfactory installation of this equipment be sure to observe "Cable Terminal
Information” regarding power cable connection tightness and "Requirements for Upstream

DANGER!!!!

Circuit Protective Devices" located in this manual.

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.

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3.2. 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 short­time/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.

3.3. 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 engineered drawings attached to
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.

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To change the transfer switch voltage, refer to “INSTRUCTIONS TO CHANGE SYSTEM

VOLTAGE ON TS870 SERIES TRANSFER SWITCHES WITH TSC 80E
CONTROLLER” (attached as “Appendix B). Contact Thomson Technology for further

information as may be required.

3.4. SYSTEM PHASING-HIGH LEG DELTA SYSTEMS

For systems using high leg delta 240V 3 phase 4 wire systems, connection of supply
conductors must have the correct phasing as shown below.

WARNING

Failure to match correct system
phasing will result in serious damage
to the TSC 80E controller.

Automatic Transfer

Switch (Utility Supply)

PH A

(UA)

PH B

(UB)

PH C

(UC)

Neural

(N)

B

(Orange)

(High Leg)

208V

C

(Yellow)

A

(Red)

240V 240V

120V 120V

N

(White)

Where transfer switches are supplied without power isolation transformers (PT1 &
PT2) for ATS control logic it is essential that the orientation of phase conductors of

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TS 870 TRANSFER SWITCH

the supply source be arranged such that the phase of highest potential with respect
to ground is not connected to the power supply inputs to the controller (A Phase for
both supplies). Failure to do so will result in equipment damage.
Per NEC Article 384-3 (f) “The B phase shall be that phase having the higher
voltage to ground on a 3-phase, 4-wire delta connected systems.”

3.5. 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
Technology

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.

3.6. DIELECTRIC TESTING

Do not perform any high voltage dielectric testing on the transfer switch with the TSC
80E 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 80E must be removed if high voltage dielectric testing is performed on the
transfer switch.

3.7. INSTALLATION OF OPEN TYPE TRANSFER SWITCHES

Please refer to the factory for additional information.

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3.8. MOUNTING OF ENCLOSED TRANSFER SWITCHES

Model TS840, TS870 and TS880 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 Technology offers
in NEMA 1, NEMA 2, NEMA 3R and NEMA 4X for the above listed product. If a
customer requests a custom enclosure it would not be covered under the generic
certificate; if certification were a requirement Consult factory before ordering.
The Automatic Transfer Switches are qualified to the highest known level in North
America; based on site class D. Specifically this is a spectral acceleration of 342%.
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 2006 or latest version.

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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.

4. GENERAL DESCRIPTION

Thomson Technology 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 over current protection.

The TS 870 series transfer switches use a type TSC 80E microprocessor based controller, which
provides all necessary control functions for fully automatic operation. The TSC 80E controller is
mounted on the door of the transfer switch enclosure and operating status is shown via LED lights.
For further information on the TSC 80E Transfer Controller, refer to separate instruction manual
PM063.

The power switching devices used for the Utility and Generator sources are operated by an
electrically driven motor mechanism in the transfer switch. The transfer switch motor utilizes the
power from the source to which the electrical load is being transferred. The mechanism provides a
positive mechanical interlock to prevent both power switching units from being closed at the same
time, which allows an open transition, “break-before-make” transfer sequence. The TSC 80E

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transfer controller provides a standard neutral position delay timer to allow adequate voltage decay
during transfer operation to prevent out of phase transfers.
Note: For the purpose of this manual, the following standard nomenclature is utilized:

• Utility: to indicate the source of primary power

• Generator: to indicate the source of standby power

• Power switching device: to indicate the transfer switch power switching device

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TS 870 TRANSFER SWITCH

1

N - MOLDED CASE SWITCH C/W ELECTRONIC

2

2

1

1

N - MOLDED CASE SWITCH C/W ELECTRONIC

5

17. ENCLOSURE TYPE

1

2

3

3

4

5

4

4.1. PRODUCT MODEL CODE

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

1-3. SERIES 15 . VOLTAGE 18. UTILITY SWITCHING DEVICE

TS - TRANSFER SWITCH

4 & 5. MODEL

87 - 870 SWITCH

6. POLES

2 - 2 POLE
3 - 3 POLE
4 - 4 POLE J - 240/416

7. CONFIGURATION TYPE

A - ATS
X - SPECIAL

8 - 11. AMPERAGE

0100 P - 208 & GF TRIP (250-1200A)
0150 Q - 220
0200
0250 U - 416 A - STANDARD
0400 V - 480 X - SPECIAL
0600 W - 600
0800 X - SPECIAL
1000 A - STANDARD
1200

12. APPLICATION

A - STANDARD
B - SERVICE ENTRANCE
X - SPECIAL A - NEMA1, ASA #61 GREY

13. OPERATION TYPE

1 - OPEN TRANSITION D - NEMA3R SD, ASA #61 GREY
2 - MANUAL ELEC. OP. E - NEMA3R DD, ASA #61 GREY
X - SPECIAL F - NEMA3RX/4X DD AT 800A AND ABOVE AND N4 AT 600A

14 . SAFETY STANDARDS

A - UL 1008 H - NEMA 3RXDD (ALUMINUM)
B - CSA C22.2 NO 178
X - NOT APPLICABLE X - SPECIAL

1 2 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

T S 8 7

1f 3 WIRE

D - 120/240 M - MOLDED CASE SWITCH C/W THER-MAG

3f 4 WIRE (GROUNDED NEUTRAL)

E - 120/208
F - 127/220 TRIP (250-1200A)

G - 120240 1 (DELTA)
H - 220/380
S - 230/400

K - 254/440 K - MOLDED CASE SWITCH (100 - 1200 A)
M - 277/480
N - 347/600
Y - MULTIVOLTAGE

Customer to specify voltage when ordering

3f 3 WIRE

R - 240

16. CONTROLLER

3 - TSC 80e C - ALTERNATE C (1000-1200A)
7 - NONE (MANUAL) D - ALTERNATE D (1000-1200A)

B - NEMA2, ASA #61 GREY
C - NEMA12, ASA #61 GREY

(306 STAINLESS STEEL)

G - NONE (OPEN STYLE)

ASA #61 GREY

(STOCK SWITCHES ONLY)

1

K - MOLDED CASE SWITCH (100 - 1200 A)

TRIP (100-200A)

P - MOLDED CASE SWITCH C/W ELECTRONIC

& GF TRIP (250-1200A)

19. GENERATOR SWITCHING DEVICE

M - MOLDED CASE SWITCH C/W THER-MAG

TRIP (100-200A)

TRIP (250-1200A)

P - MOLDED CASE SWITCH C/W ELECTRONIC

20. POWER CONNECTIONS

21. ATS CONNECTION CONFIGURATION

B - ALTERNATE B (1000-1200A)

NOTES

MULTI-VOLTAGE CAPABLE
FOR 50 Hz APPLICATION
STANDARD ENCLOSURE RATING IS N3R

AND BELOW

ONLY AVAILABLE 800A AND ABOVE
240V MAX

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4.2. TYPICAL COMMISSIONING PROCEDURES

CAUTION:

Commissioning procedures must be performed by qualified
personnel only. Ensure the Automatic Transfer Switch
(ATS) Control Circuit Isolation Plug is 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 (attached as “Appendix A ”) is provided for

general information only pertaining to typical site installations and applications. Contact
Thomson Technology for further information as may be required.

5. GENERAL THEORY OF OPERATION

5.1. STANDARD AUTOMATIC TRANSFER SWITCH

5.1.1. NORMAL OPERATION

When utility supply voltage drops below a preset nominal value (adjustable from
70% to 100% 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 60 sec.) an engine start
signal (contact closure) will be given.

Once the engine starts, the transfer switch controller will monitor the generator
voltage and frequency levels. Once the generator voltage and frequency rises
above preset values (adjustable from 70% to 95% of nominal), the engine warm-up
timer will be initiated. Once the warm-up timer expires (adjustable from 0 to 60
sec.), 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.

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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 the preset values (adjustable from 70% to 95% of nominal) on all
phases, a transfer return delay circuit will be initiated. Following expiry of the Utility
Return Timer (adjustable from 0 to 30 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 load 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 (adjustable from 0
to 60 seconds).

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 30 minutes), the engine start signal will be removed (contact opening) to
initiate stopping of the generator set.

5.2. SERVICE ENTRANCE AUTOMATIC TRANSFER SWITCH

Note: This applies only to service entrance transfer switches

5.2.1. NORMAL OPERATION

Under normal conditions, the load is energized from the utility supply through the
closed utility transfer power switching device. If the utility power fails, the generator
will start and the load will be re-energized via the closed generator transfer power
switching device.
In the normal operating mode, the Service Disconnect switch shall be in the
“energized” position.

5.2.2. OVER CURRENT TRIP

Should the utility power switching device trip open due to an over current condition,
TSC 80E transfer controller will initiate an engine start signal and will permit transfer
of the load to the generator supply. The utility source will be locked out and the load
will remain on the generator supply until the TSC 80E alarm signal is manually reset.
Refer to the TSC 80E Instruction Manual for further details on Transfer Fail
operation.

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Should the generator power switching device trip open due to an over current
condition, TSC 80E transfer controller will initiate transfer of the load to the utility
supply. The generator source will be locked out and the load will remain on the utility
supply until the TSC 80E alarm signal is manually reset.

5.2.3. SERVICE DISCONNECT PROCEDURE

To perform a service disconnect (i.e. to disconnect the utility and generator
supplies), the following procedure is required:

1. Move the "Service Disconnect" control switch located on the door of the
transfer switch to the "Disconnected" position.

2. Verify that the "Service Disconnected" pilot light is illuminated. If the Light

is illuminated, the service has been successfully disconnected and it is safe
to perform any maintenance procedures as required. In this condition, the

transfer switch is in the neutral position, with both utility and generator
transfer power switching devices open. The transfer switch will remain in this
condition, regardless of condition of the utility and generator supplies (i.e. if
the utility power fails, the generator will not receive a start signal, nor will the
transfer switch move to the generator position). NOTE: If the Service

Disconnect Light is not illuminated, additional procedures are required (refer
to the following procedure #5.2.4).

3. Attach safety lockout padlock to the "Service Disconnect" control switch to
prevent unauthorized change in operating condition and verify transfer switch
door is locked closed. If the door is not locked, turn and remove door key.

WARNING!

Close and lock the transfer switch enclosure door
before connecting power sources.

4. To reenergize the load, remove the padlock(s) from the service disconnect
control switch, and move the switch to the energized position. The transfer
switch will immediately return to the utility or generator supply if within normal
operating limits.

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