Motor thermostat, Serial communications input, 8 motor thermostat – Pulsafeeder Pulsar DLCM User Manual
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5.8 Motor Thermostat
The motor thermostat has been supplied as an equipment safety measure. This allows the DLCM pump
motor to operate without the danger of overheating the motor windings.
In the event that the internal temperature of the motor exceeds the motor manufacturer’s specification,
the DLCM can be configured to:
a) Turn the motor off.
b) Sound an alarm.
c) Restart the motor when the temperature lowers to a safe level.
For more information about the Motor Thermostat settings, refer to Section 7 – General Operation:
Motor Thermostat Setup .
To connect the Motor Thermostat to the DLCM, connect the two thermostat wires (typically these
wires are a smaller gauge wire) coming from the pump motor to the connection point labeled ‘3–
THERM [+]’ and ‘4–THERM [-]’ on connector J–10 CONTROL (refer to Figure 8).
5.9 Serial Communications Input
The Serial Communications input is used to communicate digitally with the DLCM. It allows remote
control and, if so configured, can be used to replace the analog input and output to allow one or more
DLCM’s to be slaved to a single DLC, DLCM, PLC, or PC master.
Figure 9 – Typical Serial Communications Connections
Use Belden™ Type 1590A data twist cable or equivalent. RJ-11 connectors (not supplied) are used to
plug into jacks J7 & J8 (refer to Figure 9).
The DLCM uses a 4-wire RS-485 network. This uses two wires for transmit and two wires for receive.
The RS-485 specification limits the total network length to 1200M (4000 ft). It also requires termination
resisters at both the first and last device.
Line Terminators can be constructed according to the drawing above.