THOMSON TSC 7320 Service manual

PM180 Rev 0 23/02/10
TSC 7320
TRANSFER SWITCH
CONTROLLER
INSTALLATION, OPERATING &
SERVICE MANUAL
9087A - 198th Street, Langley, BC, Canada V1M 3B1 · Telephone (604) 888-
0110
Email: [e-mail] · www.thomsonps.com

TABLE OF CONTENTS
1. INTRODUCTION 1
1.1. PRODUCT REVISION HISTORY 1
1.2. GENERAL DESCRIPTION 1
2. INSTALLATION 2
2.1. GENERAL INFORMATION 3
2.2. NOTES TO INSTALLER 3
2.3. MOUNTING 3
2.4. AC VOLTAGE SENSING INPUT 5
2.5. AC CURRENT SENSING INPUT 6
2.6. AC CONTROL POWER INPUT 7
2.7. AUXILIARY DC CONTROL POWER INPUT 7
2.8. PROGRAMMABLE INPUTS 7
2.9. PROGRAMMABLE OUTPUTS 7
2.10. EXTERNAL ATS CONTROL WIRING 7
2.11. REMOTE START CONTACT FIELD WIRING 8
2.12. COMMUNICATION CABLE INSTALLATION 9
2.13. DIELECTRIC TESTING 9
3. DESCRIPTION 10
3.1. FRONT PANEL LEDS 10
3.2. CONTROLLER INPUT CONNECTIONS 11
3.3. CONTROLLER OUTPUT CONNECTIONS 12
3.4. ATS OPERATION MODE DESCRIPTIONS 13
3.5. AUTOMATIC SEQUENCE OF OPERATION 15
3.5.1. OPEN TRANSITION TRANSFER (NEUTRAL DELAY) 15
3.5.2. OPEN TRANSITION (FAST, IN-PHASE) TRANSFER 16
3.5.3. CLOSED TRANSITION (FAST, IN-PHASE) TRANSFER 17
3.6. DISPLAY PAGE DESCRIPTIONS 19
3.6.1. STATUS PAGE 20

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3.6.1. GENERATOR PAGE 20
3.6.2. MAINS PAGE 20
3.6.3. ALARMS PAGE 20
3.6.4. EVENTS LOG PAGE 21
3.6.5. SCHEDULE PAGE 21
3.6.6. PLC INSTRUMENTATION PAGE 21
3.6.7. CURRENT METERING PAGE 22
3.6.8. SYNCHROSCOPE PAGE 22
3.6.9. ABOUT PAGE 22
4. OPERATING INSTRUCTIONS 23
4.1. DISPLAY SCREEN NAVIGATION 23
4.2. ON LOAD TEST INSTRUCTIONS (UTILITY POWER FAIL SIMULATION) 24
4.3. OFF LOAD TEST INSTRUCTIONS (GENERATOR NO LOAD TEST) 24
4.4. OPEN/CLOSED TRANSITION TRANSFER OPERATION 25
4.4.1. Open Transition IN-SYNC Transfer Operation (Model X) 26
4.4.2. CLOSED TRANSITION REANSFER (FAST TRANSFER MODEL 3) 26
4.5. TRANSFER FAIL ALARM RESET 27
4.6. SERVICE DISCONNECT MODE 27
4.7. PHASE SEQUENCE PROTECTION ALARM RESET 27
5. PROGRAMMING INSTRUCTIONS 28
5.1. PASSWORD SECURITY DESCRIPTION/LOGIN 28
5.1.1. NON-RESTRICTED SETTINGS 28
5.1.2. RESTRICTED SETTINGS 29
5.2. SYSTEM TIME/DATE ADJUSTMENT 30
5.3. VOLTAGE CHANGE PROCEDURE 31
5.4. EXERCISE TIMER SETUP 33
5.4.1. ADDING / EDITNG NEW EXERCISE SCHEDULE EVENT 33
5.5. MULTI-STAGE LOAD SHED CONTROL 34
5.6. SYSTEM SETTINGS 35
5.6.1. OPEN TRANSITION 35
5.6.2. MANUAL OPERATION 35
5.6.3. REMOTE OFF LOAD TEST 36
5.6.4. REMOTE ON LOAD TEST 36
6. FACTORY DEFAULT PROGRAMMING 37

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7. TSC 7320 WIRING PIN CONNECTIONS 38
8. TROUBLESHOOTING 39
9. REPLACEMENT PARTS 44
10. PRODUCT RETURN POLICY 45
11. NOTES 46

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1. INTRODUCTION
1.1. PRODUCT REVISION HISTORY
The following information provides an historical summary of changes made to this product since
the original release.
Controller Firmware Version
R0, 23/02/10 Original Release
Operating & Service Manual Version
Rev 0 23/02/10 Original release
Related Product Instruction Manuals
 TSC 7320 ModbusTM Communication, PM174
 TS 870 TSC 7320 Installation, Operating, & Service Manual, PM175
 TS 870 TSC 7320 Quick Start Guide, PM173
 TS 970 TSC 7320 Quick Start Guide, PM176, PM177
 TS 880 TSC 7320 Installation, Operating, & Service Manual, PM178
Contact Thomson Power Systems to obtain these instruction manuals. A soft-copy of the most
current versions of these manuals are available at www.thomsonps.com.
1.2. GENERAL DESCRIPTION
The TSC 7320 controller utilizes a powerful ARM microprocessor, which provides high accuracy
for all voltage sensing and timing functions. The TSC 7320 is factory configured to control all the
operational functions and display features of the automatic transfer switch. All features of the
TSC 7320 are fully programmable from the front panel graphical screen display and are security
PIN protected.

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2. INSTALLATION
CAUTION
This equipment contains static sensitive parts. Please observe the following
anti-static precautions at all times when handling this equipment. Failure to
observe these precautions may cause equipment failure and/or damage.
The following precautions must be observed:
 Discharge body static charge before handling the equipment (maintain exposed body contact
with a properly grounded surface while handling the equipment, a grounding wrist strap
can/should also be utilized)
 Do not touch any components on the printed circuit board with your hands or any other
conductive equipment
 Do not place the equipment on or near materials such as Styrofoam, plastic and vinyl. Place
the equipment on properly grounded surfaces and only use an anti-static bag for transporting
the equipment

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2.1. GENERAL INFORMATION
NOTE
Installations should be done in
accordance with all applicable electrical
regulation codes as required.
The following installation guidelines are provided for general information only pertaining to
typical site installations. For specific site installation information, consult Thomson Power
Systems as required.
NOTE: Factory installations of Thomson Power Systems supplied transfer switches that have
been tested and proven, may deviate from these recommendations.
2.2. NOTES TO INSTALLER
If the transfer switch has programmable/multi-tap system voltage capability (refer to electrical
schematic), confirm the transfer switch has been configured for the system voltage.
WARNING
Failure to confirm and match transfer
switch voltage with the system voltage
could cause serious equipment damage.
If the transfer switch requires reconfiguring, the TSC 7320 controller will also require
reprogramming.
CAUTION
Qualified personnel must complete all installation and/or service work performed
only. Failure to do so may cause personal injury or death.
2.3. MOUNTING
When the TSC 7320 controller is supplied as part of a Thomson Power System automatic
transfer switch, the controller is mounted on the ATS door with screw clamps that are supplied
with the controller. When the TSC 7320 GHC is supplied loose for door mounting, it requires a
rectangular door cut-out that is 13.5” W x 7.75” L.

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2.4. AC VOLTAGE SENSING INPUT
The TSC 7320 can accept direct AC voltage sensing inputs on the generator, utility and load
from 120-600VAC (nominal). Sources up to 600VAC (phase to phase) can be connected wye
or delta with grounded or ungrounded neutral without the need for additional sensing
transformers. The TSC 7320 voltage sensing can support the following types of electrical
systems:
Refer to SECTION 5.3 for system voltage programing instructions.

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2.5. AC CURRENT SENSING INPUT
The TSC 7320 can accept 4 x 0 - 5Aac current inputs from the secondary windings of current
transformers (CT’s). CT’s are to be connected on the load side of the ATS (Phase A, B, C & N).
WARNING
Do not unplug any current transformer inputs while
energized as severe high voltages can develop which may
cause personal injury or death.

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2.6. AC CONTROL POWER INPUT
The TSC 7320 requires 24VDC control power input voltage. Independent AC control power is
required from both utility and generator supplies via potential transformers. The potential
transformers then supply voltage to 24VDC power supplies. The TSC 7320 typically requires
approximately 12VA AC power for internal control circuits but may draw up to 30VA dependent
upon external loads connected. The maximum external load is limited by output contact ratings
(i.e. 10A resistive, 120/250VAC). Total AC control power requirements for each supply must be
determined by adding both internal and external load requirements.
2.7. AUXILIARY DC CONTROL POWER INPUT
The TSC 7320 can be additionally supplied with 24VDC auxiliary control power input voltage for
applications requiring continuously energized control and display features. The maximum input
power draw is 25W. The 24VDC power must be from a regulated/filtered DC supply with
maximum +-10% voltage range.
2.8. PROGRAMMABLE INPUTS
The TSC 7320 provides Qty 16 Programmable Inputs. Each input is activated by external contact
closure to common (i.e. DC Negative ground). Each programmable input can be independently
programmed to different functions. Refer to SECTION 3.2 for more information.
2.9. PROGRAMMABLE OUTPUTS
The TSC 7320 is provided from the factory with 8 programmable digital outputs (24VDC) and 2
programmable dry contact outputs. See SECTION 3.3 for more information
Interposing relays are required between the TSC 7320 outputs and the end device if loads
exceed the output current rating.
2.10. EXTERNAL ATS CONTROL WIRING
As a minimum, all external control wiring to/from the ATS must conform to the local regulatory
authority having jurisdiction on electrical installations. Specific wire sizes listed below are for
typical circuits of distances up to 500ft (150m)1, are as follows:
Utility or Generator Voltage Sensing #14 AWG (2.5mm2)
Transfer output signals #14 AWG (2.5mm2)
Remote Start Contact for Engine Controls #14 AWG (2.5mm2)
NOTE: For long control wire runs or noisy electrical environments the control wires
should be twisted & shielded with a suitable drain wire. The shielded cable drain wire
must be grounded at one end only. The drain wire grounding location may vary as micro-
processor controllers generally exist at both ends (engine generator set & transfer

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switch) and one may be more susceptible depending on the level of induced noise. The
most susceptible controller will require the shield ground point as close as possible to
the controller. Wire runs from 500ft to 1000ft should be twisted and shielded and
increased to #12 AWG where total loop resistance is greater than 5 ohms.
1For distances exceeding 1000ft. (300m) consult Thomson Power Systems
2.11. REMOTE START CONTACT FIELD WIRING
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.
2.8.1. Remote start contact wires (2 #14 AWG (2.5mm2)) should be run in a separate
conduit (ferromagnetic type) and in all cases separated from any AC wiring.
2.8.2. Avoid wiring near AC power cables to prevent pick-up of induced voltages.
2.8.3. An interposing relay may be required if field-wiring distance is excessively long
(i.e. greater than 1000 feet (300m)) and/or if a remote contact has a resistance
of greater than 5.0 ohms. In extremely noisy environments, the wire run lengths
indicated may not provide reliable operation and can only be corrected by the
use of an interposing relay. The interposing relay is generally installed at the
engine controls and utilizes DC power. It is strongly suggested that the ground
return wire of the interposing relay be used for the interface to the TSC 7320
remote start contact, this will ensure integrity of the DC power supply to the
engine generator set controls in the event of a shorted or grounded wire remote
start interface wire.
2.8.4. The remote start contact provided is voltage free (i.e. dry contact). Exposing the
remote start contact to voltage or current levels in excess of its rating will damage
the transfer controller.

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2.12. COMMUNICATION CABLE INSTALLATION
Communication cable wiring from the controller’s communication port must be suitably routed
to protect it from sources of electrical interference. Guidelines for protection against possible
electrical interference are as follows:
 Use high quality, shielded cable only with drain wire grounded at the controller end
only
 Route the communication cable at least 3 M (10’) away from sources of electrical
noise such as variable speed motor drives, high voltage power conductors, UPS
systems, transformers, rectifiers etc.
 Use separate, dedicated conduit runs for all communication cables. Do not tightly
bundle communication cables together in the conduit. Conduit should be
ferromagnetic type near sources of possible electrical interference. The entire length
of conduit should be grounded to building earth ground
 When communication cables must cross over low or high voltage AC power
conductors, the communication cables must cross at right angles and not in parallel
with the conductors
For additional information on protection against electrical interference, contact Thomson Power
Systems factory.
2.13. 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/DC
control fuses or control/sensing circuit isolation plugs connected to the TSC 7320 must be
removed/disconnected if high voltage dielectric testing is performed on the transfer switch.

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3. DESCRIPTION
The TSC 7320 controller is an all in one unit and does not require any communication cables to operate.
The controller has 13 buttons on the front of the controller that can be used to change what the controller
is displaying, changing the settings, and control the mechanism. See the figure below for more
information.
3.1. FRONT PANEL LEDS
The front panel of the controller has 12 LEDs that display the position of the ATS, source
availability, current controller mode, and some inputs / outputs.
The front panel LEDs will stay illumined while the given status is true except for the Alarm
LED, which will flash if there is an alarm that is present. See SECTION 4.5 for more
information on alarms and how to clear them.

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3.2. CONTROLLER INPUT CONNECTIONS
The TSC 7320 is provided from the factory with 14 programmable inputs with default settings
per table shown below. 8 of the inputs are digital inputs, and the other 6 are analogue inputs
that can also be programmed to be more digital inputs. Refer to the TSC 7320 Manual for further
information on programming changes as required.
NOTE: All control wiring required for any remote input connection must be made directly to the
door mounted TSC 7320 as per drawing below. All input wire cabling that may be installed must
be suitably routed and protected across the door hinge to prevent possible mechanical damage
upon door opening and/or door closing. Switch Control Unit internal PCB is shown in the
following diagram:
WARNING: Do not apply any voltage across the input terminal and DC common as this
will cause damage to the TS 7320 controller. Connect only a dry (i.e. voltage-free) contact.

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3.3. CONTROLLER OUTPUT CONNECTIONS
The TSC 7320 is provided from the factory with 8 programmable digital outputs and 2 programmable
dry contact outputs with default settings per the table shown below. Refer to the TSC 7320 Manual for
further information on programming changes as required. The Digital outputs are rated 2A @ 24VDC
resistive. Dry output contacts are rated at 8 amps @ 250Vac resistive. One of the dry contacts are
normally closed and the other contact is normally open.
NOTE: All control wiring required for any programmable output connections must be made directly to
the door mounted TSC 7320 controller as per drawing below. All output wire cabling that may be
installed must be suitably routed and protected across the door hinge to prevent possible mechanical
damage upon door opening and/or door closing.
WARNING: Do not apply any voltage across the output contacts as this will cause damage to
the TSC 7320 controller. Connect a load in series with applicable voltage/current as specified.

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3.4. ATS OPERATION MODE DESCRIPTIONS
Mode Description ATS Mechanism
Control Outputs
Engine Start Output
AUTO ATS automatically transfers to Generator (Source 2) during a
Utility (Source 1) failure and automatically returns power to utility
once restored
Outputs automatically operate
ATS mechanism per automatic
sequence of operation
Output contact closes to start
engine during a utility (source
1) failure and opens to stop
engine once utility power has
transferred back to the load.
STOP MODE ATS will immediately start transferring to utility and stay there. The
ATS will not automatically operate during a utility power failure
Outputs momentarily energize to
move ATS mechanism to the
Utility position. If the mechanism
is moved away from Utility, the
controller will automatically move
it back to Utility.
Output is disabled - engine will
not start during a utility power
failure1
Engine will stop if it was
previously running
TEST MODE ATS will not automatically operate during a utility power failure,
and The ATS will transfer to utility if there is a gen power failure.
ATS cannot be operated manually as the controller will keep the
breaker on utility.
Outputs momentarily energize to
move ATS mechanism to the
Utility position. If the mechanism
is moved away from Utility, the
controller will automatically move
it back to Utility.
Output is enabled but engine
will not start during a utility
power failure1.
Engine will continue to run
unless there is a fault.
MANUAL ATS will not automatically operate during a utility power failure,
and The ATS will transfer to utility if there is a gen power failure.
ATS cannot be operated manually as the controller will keep the
breaker on utility.
Outputs momentarily energize to
move ATS mechanism to the
Utility position. If the mechanism
is moved away from Utility, the
controller will automatically move
it back to Utility.
Output is enabled but engine
will not start during a utility
power failure1.
Engine will continue to run
unless there is a fault.
SERVICE
DISCONNECT
(Service
Entrance
Only-US
Market ATS)
ATS transfers to neutral position to disconnect power to the load.
ATS will not automatically operate during a utility power failure.
Note:
When the Service Disconnect signal is removed, the transfer
switch will immediately return to the utility, and the controller will
remain in STOP mode. When required, put the controller back in
Auto mode.
Outputs momentarily energize to
move ATS mechanism to the
neutral position.
Output is disabled - engine will
not start during a utility power
failure1. Engine will stop if it
was previously running
ON LOAD
TEST
When ONLOAD TEST mode is initiated, a utility power failure
condition will be simulated which will cause engine to start and
ATS will transfer to generator supply. When TEST mode is
terminated, ATS will transfer back to utility supply and engine will
stop
Outputs automatically operate
ATS mechanism per automatic
sequence of operation
Output contact closes to start
engine during the ONLOAD
TEST mode. Output
automatically opens when test
mode is terminated and ATS is
back on utility power
EXERCISE
ON LOAD
TEST
When ONLOAD TEST mode is initiated, a utility power failure
condition will be simulated which will cause engine to start and
ATS will transfer to generator supply. When TEST mode is
terminated, ATS will transfer back to utility supply and engine will
stop
Outputs automatically operate
ATS mechanism per automatic
sequence of operation
Output contact closes to start
engine during the ONLOAD
TEST mode. Output
automatically opens when test
mode is terminated and ATS is
back on utility power
MANUAL OFF
LOAD
TEST
When OFF LOAD TEST mode is manually initiated, engine will
start and run, but the ATS will not transfer to the generator. When
OFF LOAD TEST mode is terminated, engine will stop
Outputs do not change state
even if utility or generator supply
fails
Output automatically closes to
start engine during the OFF
LOAD test mode. Output
automatically opens when test
mode is terminated
EXERCISE
OFF LOAD
TEST
When OFF LOAD TEST mode is initiated, engine will start and
run, but the ATS will not transfer to the generator. When OFF
LOAD TEST mode is terminated, engine will stop
Outputs do not change state
unless utility or generator supply
fails in Off Load test mode
Output automatically closes to
start engine during the OFF
LOAD test mode. Output
automatically opens when test
mode is terminated
EXERCISE
SCHEDULE
When an EXERCISE SCHEDULE occurs, the ATS will perform an
exercise test on the pre-selected calendar date and time. The
Generator will operate on load or off load as selected and will
continue to run for the Exercise duration period as selected. If a
re-occurring Exercise mode is selected, ATS will repeat an
exercise test based on the calendar dates and times as selected.
Outputs operate ATS mechanism
per automatic sequence of
operation if programmed for ON
LOAD TEST operation.
Output contact closes to start
engine during the EXERCISE
test mode. Output
automatically opens when
exercise mode is terminated

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1 The TSC 7320 requires continuous control power (i.e. utility/gen power on, or 24VDC aux power on) to keep the automatic engine
start output disabled. If control power is de-energized, the engine start output will close in approximately 3 minutes, once its internal
control power reservoir de-energizes. This in turn will cause a repeating engine start/stop event every 3-4 minutes. To prevent engine
start/stop cycling condition upon loss of control power, the local engine control panel should be selected for the OFF operating mode.

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3.5. AUTOMATIC SEQUENCE OF OPERATION
3.5.1. OPEN TRANSITION TRANSFER (NEUTRAL DELAY)
NOTE: For specific device settings and ranges, refer to SECTION 6 - Factory Default
Programming.
NOTE: Time delays indicated below are factory default settings only. Refer to TSC 7320 manual for alternate time delay settings available on
the TSC 7320 Controller
UTILITY POWER
FAIL
When voltage drops on any phase of the utility supply below 85% of rated voltage, a generator start sequence will
be initiated
GEN START The generator will start following expiry of the 2 second Gen Start timer
GEN WARMUP A generator warmup period will be initiated once the generator starts running, and will not transfer until the timer
expires, or a fault occurs
TRANSFER TO
GEN
The load will transfer to the generator supply following expiry of the 2 second Gen Warmup timer
UTILITY POWER
RETURN
When utility power is restored to above 90% rated voltage on all phases, a utility return timer sequence will be
initiated
TRANSFER AWAY
FROM
GENERATOR
The load will transfer away from the generator supply following expiry of the 300 second utility return timer
TRANSFER TO
UTILITY
Once the load transfers off of the generator supply, the load will re-transfer back onto the utility supply following
expiry of the 3 second neutral delay timer
GEN COOLDOWN The generator will automatically stop following expiry of the 300 second cooldown timer.

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3.5.2. OPEN TRANSITION (FAST, IN-PHASE) TRANSFER
NOTE: This transfer operation type is applicable to Power Contactor type ATS or those
with spring-charged motor operated breaker types. For specific device settings and
ranges, refer to SECTION 6 Factory Default Programming.
Under normal 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 on any phase, an engine
start delay circuit will be initiated. Following expiry of the engine start delay period an
engine start signal (contact closure) will be given.
Once the engine starts, the transfer switch controller will monitor the generators voltage
and frequency levels. Once the generator voltage and frequency rise above preset
values, a warmup time delay will be initiated. Once the warmup timer expires, the transfer
to utility supply signal will be removed (i.e. contact opening) and 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) 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 the preset values on all phases, a utility return delay timer will be initiated.
Following expiry of the utility return timer, the TSC 7320 controller will verify the
difference of voltage, frequency and phase angle between the generator and utility
sources, and once an in-phase condition is detected, the generator power switching
device will open, then the utility power switching device will close within ~150
milliseconds to complete the fast (in-phase) break-before-make re-transfer sequence.
An engine cooldown timer circuit will be initiated once the load has successfully re-
transferred back onto the utility supply. Following expiry of the cooldown delay period
the engine start signal will be removed (remote start contact opened) to initiate stopping
of the generator set.