Product Manual

2
1.1 INTRODUCTION
This manual has been prepared especially for the purpose of familiar-
izing personnel with the design, application, installation, operation
and servicing of the applicable equipment. Read the manual carefully
and comply with all instructions. This will help to prevent accidents or
damage to equipment that might otherwise be caused by careless-
ness, incorrect application, or improper procedures.
Every effort has been expended to make sure that the contents of this
manual are both accurate and current. The manufacturer, however,
reserves the right to change, alter or otherwise improve the product
or manual at any time without prior notice.
1.2 UNPACKING
Carefully unpack the transfer switch. Inspect closely for any damage
that might have occurred during shipment. The purchaser must file with
the carrier any claims for loss or damage incurred while in transit.
Check that all packing material is completely removed from the switch
prior to installation.
1.3 EQUIPMENT DESCRIPTION
The automatic transfer switch is used for transferring critical electrical
load from a UTILITY (NORMAL) power source to a GENERATOR
(STANDBY) power source. Such a transfer of electrical loads occurs
automatically when the UTILITY power source has failed or is sub-
stantially reduced and the GENERATOR source voltage and frequen-
cy have reached an acceptable level. The transfer switch prevents
electrical feedback between two different power sources (such as
the UTILITY and GENERATOR sources) and, for that reason, codes
require it in all standby electric system installations.
The transfer switch consists of a transfer mechanism, a control relay,
an Overload Prevention Control Board, a terminal strip and fuse
holder for connection of sensing wires.
This switch is suitable for control of motors, electric discharge lamps,
tungsten filament and electric heating equipment and the tungsten
load does not exceed 30% of the switch rating.
This UL listed transfer switch is for use in optional standby systems
only (NEC article 702).
A 100A rated switch is suitable for use on circuits capable of delivering
not more than 10,000 RMS symmetrical amperes, 250 VAC maxi-
mum, when protected by a 100A maximum circuit breaker (Siemens
types QP or BQ) or 150A maximum circuit breaker (Square D Q2,
Westinghouse CA-CAH, General Electric TQ2 and Siemens QJ2).
A 200A rated switch is suitable for use on a circuit capable of 10,000
RMS symmetrical amperes, 240 VAC when protected by a circuit
breaker without an adjustable short time response or by fuses.
The Overload Prevention Control Board is designed to prevent an
overload on the generator when it is supplying the customer loads.
See figure 1.1. Up to six loads can be managed by the OPCB; 2 air
conditioner loads and 4 other loads. The OPCB manages the loads
by “shedding” the connected loads in the event of a drop in generator
frequency (overload). Loads to be “shed” are grouped in 4 priority
levels on the OPCB.
• Priority 1 and 2 has connections for both one air conditioner and
one contactor. Both an air conditioner and a contactor can be
used at the same time if desired. To control an air conditioner,
no additional equipment is required. Internal relays interrupt the
thermostat 24VAC control signal to disable the air conditioner load.
• Priority 3 and 4 have connections for one contactor only.
• Four LEDs, located on the Overload Prevention Control Board,
will indicate when a load priority level is enabled. When loads are
connected, the LEDs will be illuminated.
• Any loads, including central air conditioners, can be controlled via
a contactor that must be purchased separately. Up to four contac-
tors can be controlled by the Overload Prevention Control Board.
(The 24 Vac or 120 Vac is supplied through the OPCB to energize
each contactor coil).
• Generator overload condition is determined by generator frequen-
cy. Loads are shed when the frequency is <58Hz for 3 seconds or
<50Hz for ½ Second (for 60Hz).
The OPCB has a Test button which forces the unit to act as if an
overload has occurred. This button operates even when the transfer
signal is inactive.
Figure 1.1 — Overload Prevention Control Board
0 Ground
194 +12V
23 Transfer
T1
NEUTRAL
A/C 1
24V
A/C 2
24V
LOAD 1
LOAD 2
LOAD 3
LOAD
4
A/C 1 & LOAD 1
LOAD
SUPPLY
LOAD
SUPPLY
1
2
1
2
2
2
2
1
1
1
1A MAX
1A MAX
1A MAX
1A MAX
A/C 2 & LOAD 2
LOAD 3
LOAD 4
Air Conditioner Connections:
Up to two A/Cs can be
controller here via their low
voltage thermostat wires
Status LEDs: Shows which
loads are currently allowed to
run
Load Connections: Up to four
loads of any type can be
controlled via these
connections. A separate
contactor module is required
2
2
1
2
1
2
1
2
2
1
1
General Information