R&M Materials Handling HOIST MONITORS - Manual (Page 24)

R&M Materials Handling, Inc.
4501 Gateway Boulevard
Springfield, Ohio 45502
P.: (937) 328-5100
FAX: (937) 325-5319
24/105
R&M Materials Handling, Inc. reserves the right to alter or amend the above information without notice.
Thermistors operating curve
0
5
10
15
20
25
30
35
40
Motor Temperature
k
o
h
m
NTC PTC Bi-metal
Over temperature
NTC and PTC: The temperature sensor’s cable must
be shielded if the cable between the unit and the
temperature sensors is longer than 10m. The cable
shield is connected to the ground of the hoist. It is
recommended to use 360 degrees shield clamps to
carry out the grounding!
Bi-metal: It is recommended to use a supplementary
relay between the unit and the thermistor. In that
case there is no need for a shielded cable and
possible disturbance is limited to the minimum.
In case third party motors are used, please consult
with the manufacturer of the motor for thermistor
details.
Motors without thermistors must be protected
against overheating by other means, e.g. a motor
protection switch.