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INSTALLATION PROCEDURE
1) A UL listed fuel/air ratio system is comprised of the following items.
a.) PPC4000, fuel/air ratio controller
b.) 60-2926, enclosure
c.) NXD410, user interface
d.) FX series servos
2) Wiring must comply with all applicable codes, ordinances and regulations.
3)
Wiring must comply with NEC Class 1 (Line Voltage) wiring.
4) To minimize interference from radio frequency energy generated by the PPC4000 control, it is
necessary that all control wiring be placed in conduit. It is recommended that all low voltage sig-
nal wiring, i.e. servos, O2 probe, pressure/temperature transducer be placed in a separate conduit
from line voltage wiring, i.e. relay outputs, line voltage digital inputs, profile select, flame safe-
guard interface signals.
5) Limit switches, interlocks and relay outputs must be rated to simultaneously carry and break
current to the ignition transformer, pilot valve(s) and main fuel valve(s) of the flame safeguard
control.
6) Recommended wire routing of lead wires:
a) Do not run high voltage ignition transformer wires in the same conduit with any other wires.
b) Do not route analog transducer cables, display communication cables, modbus cables or servo
motor cable in conduit with line voltage circuits. Use separate conduit where necessary.
7) Maximum wire lengths:
a)
Terminal inputs (Operating limits, interlocks, valves, etc.): 200 feet. (61 meters).
b)
Line voltage inputs: 500 feet (152 meters) to a normally open remote reset push-button, but
should remain within sight and sound of the burner.
c)
Modbus communications RS-485: 1000 ft (305 meters) for baud rates of 19.2kbps & below.
d) Servo & O2 probe: 200 feet (61 meters)
e)
Sensors: 100 feet (30 meters)
A good ground system should be provided to minimize the effects of AC quality problems. A prop-
erly designed ground system meeting all the safety requirements will ensure that any AC voltage
quality problems, such as spikes, surges and impulses have a low impedance path to ground. A low
impedance path to ground is required to ensure that large currents involved with any surge voltages
will follow the desired path in preferences to alternative paths where extensive damage to equipment
may occur.
NXD410 User Interface
The NXD410 is a panel mounted device. The device includes a gasket that must be properly seated
to assure NEMA 4X (IP65) rating. Packed with every NXD410 device is a gasket and remote mount-
ing bracket kit (not sold separately) containing four bracket assemblies as shown.
Replacement Fuses
23-227, F1 Main input protection
fuse, 5A, 250VAC, radial can
23-197, F3 Safety relay protection
fuse, 10A, 250VAC, radial can
