Hi, I need to replace a sensor on a machine at work, Ive checked the other sensors (fibre optic) on the machine and they are all NPN, so ive got a photoelectric sensor to go in its place which is also NPN, so it should just be a straight swap, but Im not getting the required output from the photoelectric sensor. The sensor looks to be working fine Im just having trouble getting the right signal. Both sensors (fibre & photoelectric) are 24VDC, 3 wire (Brown, Blue & Black), NPN, open logic on the PLC.
When I test the other fibre optic sensors, I test between the output from the sensor and the vdc, so I get a resistance through (0.000) when I MAKE the sensor, which means Im completing the circuit at the PLC which gives me 1 count (the sensor is for a counter) but when I do the same with the photoelectric sensor I dont get the same, I get -0.747.
Basically I need the same out-put as from the fibre optic senser to get the counter to operate. Can anybody help me understand why I can get the photoelectric sensor to work.
SICK - WTB4-3N3162 -
1028089
Photoelectric proximity sensor
And
OMRON INDUSTRIAL AUTOMATION - E3X-A11 - SENSOR, FIRBRE OPTIC, NPN
When I test the other fibre optic sensors, I test between the output from the sensor and the vdc, so I get a resistance through (0.000) when I MAKE the sensor, which means Im completing the circuit at the PLC which gives me 1 count (the sensor is for a counter) but when I do the same with the photoelectric sensor I dont get the same, I get -0.747.
Basically I need the same out-put as from the fibre optic senser to get the counter to operate. Can anybody help me understand why I can get the photoelectric sensor to work.
SICK - WTB4-3N3162 -
1028089
Photoelectric proximity sensor
And
OMRON INDUSTRIAL AUTOMATION - E3X-A11 - SENSOR, FIRBRE OPTIC, NPN