MP92, torque monitor0 pages

C-mac

®

Torque monitor MP92

Monitoring of engine torque for 3phase motors
Frequency range 10-400 Hz
Very suitable in connection with frequency converters
Analogue and relay output
Adjustable start-up time, reaction time and setpoint
Selectable current ranges: 1A, 2,5A, 5A and 10A
Produced in accordance with
and EMC regulations
C-mac® torque monitor type MP92 is used for monitoring
of the engine torque on 3-phase motors.
The unit is particularly suitable in connection with frequency converters, and it can be used on all converters using the PWM principle.
Contrary to motors connected directly to the mains
frequency, it is not possible to monitor the mechanical
load on a motor which is connected via a frequency converter, by means of a standard power monitoring unit, because both voltage, current, phase angle and frequency
must be calculated, and MP92 is developed particularly
for this purpose.
The torque monitoring principle indicates the correct mechanical load of the motor, independant of the rotation
speed, thereby making it suitable in connection with
machine monitoring and process control applications.
MP92 can be connected directly to motors with a nominal
load current up to 10 A, corresponding to approx. 5 kW.
In order to get the maximum metering accuracy you can
select between 4 different current- and 2 voltage ranges
by means of DIP-switches.
The unit is supplied with a 0-10 V output, indicating the
actual torque in percentage of the metering range, and a
1-pole relay output, which switches if the adjusted setpoint is exceeded.
Technical data:
Supply voltage:
Power consumption:
Operating temp.:
Humidity:
Ranges, current:
voltage:
frequency:
Accuracy:
Adjustments:
Start-up delay:
Reaction delay:
Setpoint:
Indications:
Red LED, Load:
Red LED. Level:
Red LED, Start:
Outputs:
Relay, setpoint:

24 VAC/DC +/- 10%
3,5 VA
-20°C to +60°C
0-90%, non-condensing
0-1A, 0-2,5A, 0-5A and 0-10A
0-250VAC and 0-500VAC
10-400 Hz
<5% (absolute), <1% (repeating)

Functional diagram:
Setpoint
Torque
Relay
LED start
LED level

ts

tr

Functional description:
When the supply voltage is connected, the relay is
activated.
When the motor starts, and the torque exceeds 5% of the
maximum torque, the start-up delay is activated, and in this
period the relay will remain activated, no matter if the
torque exceeds the adjusted setpoint.
At the end of the start-up time the LED "Level" will indicate a possible exceeding of the set-point, and if the reaction delay "tr" is exceeded, the relay releases.
Please note, that the relay activates again, when the load is
below the set limit, which means you must use the relay
output in connection with a latch circuit for the motor, if
you want the unit to disconnect the motor in case of an
overload.
Selection of metering range:
The current range must be selected in such a way, that the
normal operation current of the motor equals a metering
signal of 50-80% (5-8 volt on the output), in this way you
will get the best accuracy.
You can check the operation range by means of a voltmeter, or you can adjust on the level potentiometer to find the
operation level. If you do not want the relay to switch during this test, you can set the reaction delay to max.

0,2 - 20 seconds
0 - 20 seconds
10 - 100%
Relay active
Set limit exceeded
Start-up delay active
max. load 5A / 250V

Comadan
Produktion a/s

6-9