|Multiplexer will not power ON.
||Check the silver tag on the back of the multiplexer to determine the correct supply voltage for that model. Using a volt meter, test across pins 2 and 10 for the correct voltage reading.
|Multiplexer will not power ON. (Part 2)
||If the correct power is present on pins 2 and 10, remove the multiplexer from the socket and inspect the sides for discoloration or bulging of the plastic housing. Is the multiplexer hot or producing a strong odor? If so, the multiplexer may be damaged due to voltage spike (ie: lightning) and should be replaced.
|Output status light remains illuminated constantly.
||Verify that the correct transmitter and receiver combination are aligned with one another. (ie: the transmitter from channel 1 is matched with the receiver from channel 1) The transmitter or receiver photo eye wires may be short or open. This problem may occur anywhere between the photo eye body and the multiplexer socket. Check all splices and terminal strips for incorrect connections. If the wires are not protected by conduit in any area, check the outer sheath of the cable to see if it is brittle. If any problem areas are found in the wires, cut and splice them. Solder the connection and protect it from moisture. If lengths of the wire need to be replaced, use at least .22 gauge conductors. If no problem is found in the transmitter wires, the problem may be the multiplexer socket. Replace any defective parts.
|Output Status LED intermittently flickers
||Since the problem is intermittent, it may be challenging to diagnose the problem. If the gain setting of the multiplexer is set low, try setting it to a higher level using the gain adjustment potentiometer for the correct channel on the face of the multiplexer. Clean the face of each photo eye with a mild non-abrasive detergent. Align the photo eyes using the "string method" of stretching a string or wire between the photo eyes so that the string passes by the eye in parallel. If both photo eyes are parallel to the string, the alignment should be correct. Check for cracks or deep scratches in the face of the photo eye. Water intrusion through a crack could damage the photo eye circuitry.
|Output Status LED intermittently flickers. (Part 2)
||The transmit level adjustment of the multiplexer may be set too low for the application. First try adjusting the gain setting for both channels to a higher setting using the potentiometers on the face of the multiplexer. If this doesn't work, adjust the system power level to the "100%" setting using DIPswitch 3. (See diagram printed on the side of the multiplexer) Look closely at the receiver photoeye while the problem is occuring. If the receiver is mounted in direct sunlight, this may cause intermittent false signals. Verify that pin 7 on the multiplexer socket, also transmitter (black), shares a connection to Earth ground. If either photo eye appears damaged replace it immediately.
|Output Status LED will not turn ON.
||The transmit level adjustment of the multiplexer may be set too high for the application. First try adjusting the gain setting for both channels to a lower setting using the potentiometers on the face of the multiplexer. If this doesn't work, adjust the system power level to the "20%" setting using DIPswitch 3. (See diagram printed on the side of the multiplexer) Verify that pin 7 on the multiplexer socket, also transmitter (black), shares a connection to Earth ground. If either photo eye appears damaged replace it immediately.
|Output Status LED will not turn ON. (Part 2)
||If more than one multiplexer and sets of photo eyes are in-use in the same area, verify that there is no "crosstalk" between the systems. If multiple sets of photo eyes are operating on the same frequency, the receiver of one set may see light from the transmitter of another set. To correct this, position the photo eyes from the two systems in a way that they face away from one another.
|Multiplexer responds the opposite of its expected operation
||If the multiplexer outputs when it shouldn't and doesn't output when it should, the problem may be the setting of the "switching behavior." To correct this, adjust DIPswitch 1 and/or 2 (Whichever corresponds to the channel that seems to be functioning incorrectly) to the opposite setting and test the performance of the system. The "switching behavior" or "Light/Dark" setting of the multiplexer controls when the multiplexer activates the output, either when the receiver sees light from the transmitter (light switching) or when it doesn't (dark switching)