manual

Snow Switch
®
Model PD Pro
Instruction Manual
23735
Rev. B
06/14
[phone]
http: www.networketi.com
Environmental Technology, Inc.
1 of 30
This manual refers to the Snow Switch
®
Model PD Pro control panel manufactured
since October 31, 2013, which uses a universal (100 – 277 VAC; 50/60 Hz) power supply.
Older units use a voltage-specific power supply and have different wiring configurations.
SAFETY INFORMATION AND WARNINGS
Abnormal Odor or Smoke
In the event of smoke or a burning or abnormal odor, immediately interrupt power to the unit by
unplugging the unit or by turning off the circuit breaker protecting the unit.
Electrical Shock / Fire Hazard
Even when the heat tapes are disconnected, as long as the circuit breaker is on and power is running to
the unit, voltage is still being applied to the yellow heat tape leads. Therefore, never touch the ends of the
yellow leads or let the two leads touch each other. Do not let the two yellow heat tape leads contact any
component inside the unit.
Any installation involving electric heater wiring must be grounded to earth to protect against shock and
fire hazard. Suitable ground fault detection and interrupting systems must be in use at all times to reduce
shock and fire hazard and to protect equipment.
Electric wiring to heating elements must be installed in accordance with National Electrical Code (NEC)
requirements and all other local and applicable electrical codes and any third party standards. Follow the
installation instructions contained herein and those provided by the heater manufacturer.
Use a GFEP (Ground Fault Equipment Protection) circuit breaker on each branch circuit connected to the
ice melting system. Clearly label each circuit breaker with its function. This is vitally important when
there is more than a single point of disconnect.
Size the circuit breaker in accordance with the size of the expected load. The maximum current load for
the PD Pro is 30 Amp resistive. The PD Pro often serves as a pilot duty relay for operating high current
single- or three-phase contactors in residential or light commercial applications. This product is intended
for use in residential or light commercial applications. For larger or more critical installations, the “APS”
Series of control panels from Environmental Technology, Inc., provides a cost-effective solution offering
enhanced system design and performance features.
Make certain that the heater shield is properly grounded. Failure to do so may result in damage to the
equipment or fire.
Following installation, and prior to beginning system operation, refer to and perform the Post-Installation
Tests described in this manual.