A705-40-880 Issue B
Page 22
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Installation
3.6.4
Connect the thermal snap-switch (if fitted)
You must connect the thermal snap-switch so that the pump stops when the thermal snap-switch opens. If
you do not, there may be a risk of fire or explosion.
Incorporate a manual reset device in your control equipment. If you do not (and a fault which causes the
thermal snap-switch to open is not corrected), the pump will automatically switch on again when it cools
down. If you have started maintenance or fault finding on the pump, there will then be a risk of fire or
explosion and injury to people.
On flameproof pumps, you must use a suitable M20 x 1.5 ISO flameproof cable gland to connect to the
thermal snap-switch. If you do not, the installation will not be flameproof.
Do not connect the thermal snap-switch into an intrinsically safe circuit if the snap-switch has been
previously connected in any other type of circuit. If you do, the contacts in the snap-switch may have been
damaged, and the circuit may not be safe.
You
must
connect the thermal snap-switch to the electrical-overload control-loop of your contactor, so that the
contactor will automatically switch off the pump if it is too hot.
The thermal snap-switch will reset (that is, close again) when the pump cools down to a preset temperature
(see
). We therefore recommend that your control equipment incorporates a manual reset device so that
the pump does not automatically switch on again when it cools down.
Refer to the thermal snap-switch instruction manual for wiring details and connection instructions.
3.6.5
Connect the temperature transmitter (if fitted)
The temperature transmitter provides an indication of the pump coolant jacket temperature.
You must connect the temperature transmitter to a suitable control circuit, to shut down the pump when the coolant
jacket temperature reaches an unsafe level:
We recommend that you configure the control circuit to trip at 15 °C above the pump case operating
temperature.
If the EDP pump is part of an ATEX system, the control circuit trip settings will be defined in the ATEX System
instruction manual.
Refer to the temperature transmitter instruction manual for details of how to connect the transmitter to the control
circuit.
WARNING
Obey the safety instructions given below. If you do not, the installation may not be safe, and there
may be a risk of fire or explosion and injury to people.
WARNING
If the EDP pump is part of an ATEX system, the temperature transmitter must be connected to a
suitable control circuit as described below. If it is not, there will be a risk of fire or explosion, or
damage to the pump.