DREHMO EX-proof Actuators – Standard
Torque switches
The task of the torque switches is to switch off the DREHMO actuator if a preset torque is exceeded so that a valve with a defined closing pressure is moved into position. In the case of travel-dependent switch-off, the torque switches serve as an additional safety switch to protect the valve from mechanical overload.
Limit switch via counter gear
The counter gear consists of 2 roller units that work independently of one another. Each unit is fitted with a microswitch which is assigned to a certain direction of rotation (clockwise or anticlockwise rotation).
Limit switch via camshaft gear
Another 4 limit switches are possible in combination with a cam switch unit and reduction gear. These switches can also perform switching functions for both intermediate and limit positions.
Mechanical position indicator
The mechanical position indicator continuously shows the valve position on the device.
Blinker switch
The blinker switch is a microswitch that indicates the movement of the DREHMO actuator. The signal it issues can be processed as a running message in the control unit.
Heater
Heating is provided to prevent condensation from forming in the switch housing of the DREHMO actuator. The heating capacity is 6 watts.
Potentiometer for remote continuous position indication / Current position transmitter
These devices are used for the electrical remote indication of the actuator position. Their function is to convert the current position of the actuator to an electrical signal. This signal is either shown on a display tool or passed on to a control electronics system for further processing.
Reduction gear
The following accessories require a gear that reduces the entire actuator travel of the valve to an angle of rotation 290°:
- Limit switch in combination with camshaft gear
- mechanical position indication
- potentiometer for remote continuous position indication
- current position transmitter
