Replacing Gearbox on Automated Door system

Hello All,

I am a novice with respect to PLC's, position sensors, etc. so please forgive me if this question seems juvenile. I have to replace a gear box on a system which open and closes a very heavy door. There is a motor which contains its own gear box (100:1 ratio), and this is attached via a coupling to a right angle gear box which requires replacing. This box has a position sensor on the end of its shaft which determines when the door is fully open, which will have to be attached to the new gear box. My question is--if this sensor is screwed in or out a turn or more when it is attached to the box, will this affect the travel? Also, if the motor is manually rotated, will this also affect it with respect to the PLC? Please find attached a picture of the sensor attached to the shaft, as well as the shaft at 90 degrees in the coupling which the motor is also attached to (not shown). Any suggestions would be appreciated.

Thanks.

Not at all familiar with your gear box, but I am with your position sensor. You have a linear single turn potentiometer. The potentiometer is a very simple device. I would assum you have three wires soldered to posts sticking out of the back of the sensor. Two wires send a supply voltage to the sensor and depending on the position a voltage is output on the third wire. My recommendation would be to set the gear box in a known position and use an ohm meter to read the position of the sensor. Than after your rebuild set the gearbox to the original start position, and adjust the rotation of the potentiometer to read the same as it did when you started. Note this may still not lead to purfact results when your done, however you will be close and can either try to fine adjust the sensor or I'm sure their is a proper procedure for adjusting the stops of the door.

Let me know if you need help using an ohm meter an I will walk you thru it

Brian

Hello Brian,

Can't thank you enough for your advice! It worked exactly as you said it would. After replacing the gear box, and setting the potentiometer back to the initial votage, the door opened and closed to the correct positions. I'm always learning something from these forums. Thanks again. All the best.

TC