
SM-Universal Encoder Plus User Guide
55
Issue Number: 6
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6.7
Thermistor input
The SM-Universal Encoder Plus has a thermistor input which will allow connection of a
motor thermistor (as with the Unidrive SP drive)
This bit should be set if a motor thermistor is connected to the SM-Universal Encoder
Plus Solutions Module. The Solutions Module will trip for both
•
Over temperature
•
Thermistor short circuit.
The thermistor must have a positive temperature gradient.
For a resistance less than 50
Ω
a short-circuit trip will occur.
For a resistance greater than 3k3
Ω
an over temperature trip will occur. The trip will not
be permitted to be reset unless the resistance reduces to below 1k8
Ω
or Pr
x.12
is
returned to 0 to disable the motor thermistor check.
The resistance value of the thermistor input can be seen in Pr
x.21
. The motor
thermistor resistance value shown in Pr
x.21
is shown in 0.1% of 10k
Ω
units.
If the feedback reference is being used (Pr
x.23
) then Pr
x.21
becomes the feedback
reference and takes priority over the motor thermistor resistance indication.
x.12
Motor thermistor check enable
RW
Bit
US
Ú
OFF (0) or On (1)
Ö
OFF (0)
Update rate: Background read
Trip
Pr x.50
Thermistor trip
9
Thermistor short circuit
10
x.21
Feedback reference/ motor thermistor resistance
RO
Bi
NC
PT
Ú
-100.0 to +100.00%
Ö
Update rate: 4ms write