Control Panel - SPX Marley LW032 B Series User Manual

Caution
Warning
installation
Protect adjacent areas from excessive heat and sparks or damage
may occur.
Flanged Connection: The coil piping connections are designed for flat-face
flange fittings conforming to 150# ANSI B16.1 specifications. Full faced gas-
kets and appropriately sized bolts (by others) must be used for proper function.
5. Conduct a visual inspection of the control panel and wiring for loose con-
nections or other damage. Connect electrical supply wiring to main control
panel in accordance with wiring diagram(s) and instructions included with

control panel.

For maintenance/safety purposes, SPX recommends a lockout type
disconnect switch for all mechanical equipment. Branch circuit
protection must be provided for control panels and must meet or
exceed all NEC and local codes.
Control Panel
Variable speed operation of fan motors in cooling applications offers advantages
over traditional single or two speed motor control. Variable speed fan opera-
tion can reduce the cost of electrical energy being used and provide better
temperature control. In addition, it reduces the mechanical and electrical stress
on the motor and mechanical equipment. Electrical savings can be large dur-
ing periods of low ambient temperature when the cooling requirement can be
satisfied at reduced speeds. LW fluid coolers use Electronically Commutated
(EC) fan motors with integral variable speed capability. Multiple-fan units are
designed for synchronous variable speed operation of all fans. Fan speed and
other operating parameters of LW fluid coolers are typically controlled with a
factory mounted starter control panel.
The basic starter control panel enables programmable setpoint fan speed
control and pump starter control, and is factory wired and tested. The exte-
rior cover of the panel includes a main disconnect switch, mode selection
switches for fans and pump, and a PID controller with clear lockable cover
to control fan speed based on a programmable setpoint and the outlet fluid
temperature sensed by an RTD factory-installed in coil outlet connection. Also
included are a control transformer, fuses for all fans and the pump, disconnect
switches for individual fans, pump overcurrent protection, and a T-stat sensor
for pump control (and fan control in bypass mode). Positive Closure Damper
control, automatic discrete spray systems, and a wired 110 Volt outlet can
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