Extra equipment
Error Detector
The error detector continuously monitors the power semi conductors, motor connection and the bypass contactor. Apart form this detector reports the break down of the electronic supply voltage due to the defect in electronics, for example transformer short circuit, voltage regulation break down etc. No external errors like non symmetrical current or phase brake down etc. are reported. Additional monitoring components should be delivered in order to monitor such errors.
Phase Sequence Detector
The phase sequence detector monitors the rotational field direction and reports the wrong rotational direction by default on the error output terminals. The evaluation takes place by the user.
Current Limit
Another option of current sensor card is available for current regulation and also for current limiting. A measuring transformer is not required here. The current sensor measures the current independent of the motor size. This current determination can be used for current lead soft start up like e.g. for acceleration of heavy masses. A fixed current limiting value can be set using this sensor card and can be evaluated in the sequencer as an output contact.
In this case upon reaching a previously determined and programmed current the soft start up device gives a signal. This is necessary when for example the cutter of the planer machine becomes edgeless and the current raises and takes an order of magnitude, which is not reasonable to the motor.
These fully constructed sensor cards allow us to read the respective working currents of the motors and the breaking currents during the breaking process. Using the integrated interface RS232 display of these values can be brought to the service panel.
In a simplified version the current limit can be set using a potentiometer. A prerequisite for this purpose is however that the limiting value is determined by external measurement.
Standstill Monitor
The standstill monitor causes the turn off of the DC Braking after the motor standstill and thus avoids the unnecessary warming of motor and module. A DC-Brake is held as long as the motor does not send a corresponding signal that it is stationary. The breaking voltage is even then fed, when there is an interruption in the connection between the motor and detector, so that always a much secured breaking takes place.
There is an optional possibility to evaluate this circuit status.
PTC-Monitoring
The PTC-Operation has 3 modes and it can be selected using UP / DOWN (Settings are taken using ENTER):
1. OFF
No temperature monitoring (Select always only when no PTC is connected).
2. Automatic
Exceeding the sum resistance limit 3.60k switches off the relays contact 29-30 > Error-LED is illuminated. Going below the limit 1.60k switches the relay once again and the LED goes off.
3. Manual
Exceeding the sum of resistance limit 3.60k switches off the relay contact 29-30. Error-LED is illuminated. When it falls below the limit 1.60k there appears reset in display (Illustration 6). The temperature monitoring can be switched off using the ENTER-Button that has been activated now. This again switches on the relays, and the LED goes off, reset vanishes again and the cursor jumps to the row 1.
In addition the display shows the current PTC-resistance value. This results in a possibility of temperature estimation. Apart from this it can also be identified if the cable is broken or there is short circuit.
Jog-Function
During positioning for example it is possible to do a quick switch over of the Jog-RPM to right or left. Hereby the load dependency should be considered especially. No reversing contactors are necessary for the switch over. The reversal circuit takes place using the integrated semiconductor.
Continuous Self-Diagnosis
DSH consistently executes a self diagnosis. Following situations are monitored and displayed:
Master phase:
No synchronization is possible, Phase L1 not available
Module Short circuit:
Module L1-U , L2-V or L3-W has short circuit or the contactor is not opening
Module L3-U likewise L1-W has short circuit or the contactor is not opening.
L1 missing: only in Standby. Phase L1 is missing, Cable U missing.
L2 missing: only in standby, Phase L2 is missing, cable V missing, likewise U-V-W? missing.
L3 missing: Only in Standby, Phase 3 is missing, Cable W missing
Brake control: Interruption of freewheel module of brake
Phase monitoring during the nominal rating is in preparation.
