© ElectroCraft 2022
30
CPP-x06V48A-SA-CAN Drive User Manual
8.4
Motor Temperature Sensor
A motor over-temperature protection function is provided by the drive. The actual motor temperature is
dependent upon the temperature sensor installed in the motor. The drive is designed to be compatible
with any motor equipped with a thermistor temperature sensor. There are five different options available
for motor temperature sensing, all of which are configurable in CompleteArchitect
TM
. Select the
temperature sensor that is installed in the motor.
1. Normally Open (NO)
2. Normally Closed (NC)
3. Threshold Level
4. Negative Temperature Coefficient (NTC)
5. Positive Temperature Coefficient (PTC)
The sensor should be isolated from any voltage sources (the drive provides the necessary pull-up source)
and the low side of the sensor should be wired back to pin 8 on connector J3. See section 8.4.1 for
connection information.
Normally Open (NO) Temperature Sensing
In this instance the sensor is normally open. Once the temperature threshold is reached, the sensor will
close and pull the sensing pin (J3 pin 4) low. This can be enabled in CompleteArchitect
TM
and doesn’t
require to set any thresholds.
Normally Closed (NC) Temperature Sensing
In this instance the sensor is normally closed and holds the sensor pin (J3 pin 4) low. Once the
temperature threshold is reached the sensor will open, and the sensing pin will be pulled high internally.
This can be enabled in CompleteArchitect
TM
and doesn’t require to set any thresholds.
Threshold Level Temperature Sensing
A custom configurable threshold set in CompleteArchitect
TM
. Consult factory.
Negative Temperature Coefficient (NTC) Temperature Sensing
An NTC sensor is a resistive element whose resistance decreases with temperature.
The values of R
25
and
B
25/Tref
are inherent to the NTC sensor being applied. Their values and tolerances
will typically be included in an NTC datasheet.
-
The value of R
25
must be chosen in the range of 5k
to 50k
-
The
B
value can vary with temperature, so the user should consider the temperature threshold for
the application when choosing the appropriate
B
value and its tolerance.
CompleteArchitect
TM
includes options for entering R
25
,
B
value and the temperature threshold for the NTC
sensor that is to be used.
Positive Temperature Coefficient (PTC) Temperature Sensing
A PTC sensor is a resistive element whose resistance increases with temperature. PTC datasheets will
typically specify a temperature threshold (or switching temperature) where resistance will change sharply.
The user should choose a PTC with a temperature switching point appropriate for their motor application.
Additionally, it is required for this value to be in the range from 0.5 to 2k
. This value can be entered as
the threshold into CompleteArchitect
TM
.
For both NTC & PTC applications the drive system will have up to 6% error in accuracy for sensing
resistance. This error will be increased further by error in the temperature sensor. The user should factor
this in when considering the sensor to be used with the drive.
