Over Temperature Protection - Process Technology DQ15D Instruction Manual

Remove the panel retaining collar by inserting a flat head screwdriver
under the collar on alternating sides while sliding the collar back.
Cut a 1/4 DIN finished opening: 3.625" x 3.625" (92 mm x 92 mm) in the
panel where the DQ15D is to be mounted.
Select one or more of the knockouts from the three (3) knockouts on the
rear cover or enclosure side panels that offers the most convenient rout-
ing for external wiring. Remove the knockouts before reattaching the
rear cover or inserting the control in the panel.
Warning: Knockout removal with a hammer and a punch while the rear
cover is attached to the control may damage the control components.
Insert the DQ15D through the prepared opening and slide the retaining
collar over the case from the rear of the panel. After hand tightening the
collar, tighten the two (2) collar screws to ensure a secure fit.
Install a suitable liquid tight conduit fitting through the knockout opening
following manufacturer's instructions and install field wiring. Using the
wiring illustration on page 9, install the required input and output wires.
Use National Electric Code and local codes for determining wire sizing,
insulation, terminations, etc.
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retaining collar
collar set
screws
The factory supplied 1000 ohm RTD sensor can be extended using stan-
dard electrical hookup wire (22 awg or larger). The effect of additional
22 awg sensor wire length on the measured value is approximately 1º F
for every 65 feet.
Note: This does not apply to THERMOCOUPLES. You MUST use
specific thermocouple wire when extending the sensor wire length. Use
of incorrect extension wire can cause hazardous operating conditions.
Component failure (sensors, relays, temperature controller, etc.) in a tem-
perature controlled process can result in damage to the product, heater
over temperature, and the possibility of a fire.
To safeguard against these events, install over temperature protection.
This will interrupt the heater power supply in the event of low solution
level. Process Technology heaters include a thermal fuse standard (Pro-
tector I, II, or III) on the heater to monitor the heater's surface tempera-
ture. When wired properly, these devices cut the power to the heater in
low solution level conditions. In addition to thermal protection, Process
Technology strongly recommends the use of liquid level controls to monitor
the solution level and shut off the heaters prior to an over temperature
condition occurring.

Over Temperature Protection

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