SPX Cooling Technologies SS-NC-08A - Manual (Page 14)

Specifications Specification Value
Marley / NC Class Stainless Cooling Tower / Specifications: Options
14
Control Options
Fan Motor Starter Control Panel:
6.4 Add the following paragraph in
the Mechanical Equipment sec-
tion: Each cell of the cooling tower
shall be equipped with a UL listed
control system in a IP14 or IP56 out-
door enclosure capable of controlling
single-speed or two-speed motors as
required, and designed specifically for
cooling tower applications. The panel
shall include a main fused disconnect
or main circuit breaker with an external
operating handle, lockable in the off
position for safety. Across-the-line mag-
netic starters or solid-state soft-start
starters as required shall be controlled
with a thermostatic or solid-state
temperature controller. Door mounted
selector switches shall be provided to
enable automatic or manual control
and wired for 240VAC control. Control
circuit to be wired out to terminal
blocks for field connection to a remote
vibration switch, overload trip alarms
and remote temperature control devic-
es. The temperature controller shall be
adjustable for the required cold-water
temperature. If a thermostatic control-
ler is used it shall be mounted on the
side of the tower with the temperature
sensing bulb installed in the cold water
basin using a suspension mounting
bracket. If a solid-state temperature
controller is used the controller will be
door mounted on the control panel.
The temperature controller will display
two temperatures, one for outgoing
water and the other for set point.
Water temperature input shall be
obtained using a three-wire RTD with
dry well in the outlet water piping and
wired back to the solid-state tempera-
ture controller in the control panel.
■ If it is your opinion that the control system for the cooling tower
be part of the tower manufacturer’s responsibility, we are in
wholehearted agreement with you. Who better to determine the
most efficient mode and manner of a cooling tower’s operation—
and to apply a system most compatible with it—than the design-
er and manufacturer of the cooling tower?
Marley variable speed drives are also available for the ultimate in
temperature control, energy management and mechanical equip-
ment longevity. See specifications on page 16.