Electrical - Modine Manufacturing PTX Installation And Service Manual

INSTALLATION - ELECTRICAL CONNECTIONS
ELECTRICAL CONNECTIONS
W ARNING
1. Disconnect power supply before making wiring
connections to prevent electrical shock and equipment
damage.
2. All appliances must be wired strictly in accordance with
wiring diagram furnished with the appliance. Any wiring
different from the wiring diagram could result in a hazard
to persons and property.
3. Any original factory wiring that requires replacement must
be replaced with wiring material having a temperature
rating of at least 105°C.
4. Ensure that the supply voltage to the appliance, as
indicated on the serial plate, is not 5% greater than rated
voltage.
5. When the unit on/off toggle switch is in the "OFF" position,
supply power remains energized at the rear of the switch.
When a factory or field installed motor starting device
such as a relay or contactor are present, supply power
terminals of these components may remain energized
even in the "OFF" position. When providing service on or
near these terminals, de-energize building supply power
to the unit.
CAUTION
Ensure that the supply voltage to the appliance, as indicated
on the serial plate, is not 5% less than the rated voltage.
1. Installation of wiring must conform with local building codes, or in
the absence of local codes, with the National Electric Code ANSI/
NFPA 70 - Latest Edition. Unit must be electri cally grounded in
conformance to this code. In Canada, wiring must comply with
CSA C22.1, Part 1, Electrical Code.
2. Two copies of the unit wiring diagram are provided with each unit.
One is located in the side access control compartment and the
other is supplied in the literature packet. Refer to this diagram for
all wiring connections.
3. Make sure all multi-voltage components (motors, transform ers, etc.)
are wired in accordance with the power supply voltage.
4. The power supply to the unit must be protected with a fused or
circuit breaker switch.
5. The power supply must be within 5 percent of the voltage rating
and each phase must be balanced within 2 percent of each other.
If not, advise the utility company.
6. External electrical service connections that must be installed
include:
a. Supply power connection (115, 208, 230, 460, or 575 volts).
b. Connection of thermostats, or any other accessory control
devices that may be supplied (24 volts).
NOTE: All units with supply voltage 208V and greater must use a field
installed step-down transformer, available as a separate accessory.
7. Refer to Figure 18.1 for the junction box wiring entry location.
8. All supply power electrical connections are made in the junction
box compartment of the unit. The low voltage (thermostat and
accessory control devices) can be wired to the terminals on the
junction box.
9. Separated combustion models include a factory installed on/off
toggle switch. The function of this switch is to disconnect power to
the unit for maintenance or to shut the unit off in warm weather.
Toggle switch is rated at 15amps at 125 volts or up to 3/4 HP at
125 volts.
18
Figure 18.1 - Contractor Convenience Box with
Toggle Switch
SUPPLY CONDUIT
UNIT ON/OFF
POWER ENTRY
KNOCKOUTS
6-534.1
SWITCH
TERMINAL BOARD
FOR LOW VOLTAGE
CONTROL WIRING
INDICATOR LIGHT
GREEN: POWER
YELLOW: CALL FOR HEAT