Wiki source code of 0-10V Photocell Troubleshooting
Version 2.1 by Alexander Mott on 2026/05/07 22:21
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2.1 | 1 | Analog photocells measure light at the photocell and output a 0-10 V DC signal. On GLS-LDL photocells, this signal is output over the orange wire, with the red wire corresponding to 24 V DC input and the black wire corresponding to ground. |
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2.1 | 3 | = Reading 0% in ShowRunnerCLC™ = |
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| 5 | If an analog photocell (i.e. a 3-wire 0-10V photocell, not a Cresnet or internal occupancy sensor photocell) is defined in the ShowRunnerCLC™ configuration but you are not receiving a reading when looking at the photocell in XPanel or running the sr show photocell command, perform the following troubleshooting steps: | ||
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1.1 | 7 | 1. Verify the ShowRunnerCLC™ configuration: |
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2.1 | 8 | 11. Id should be a number without quotes matching the dictionary ID (the quoted number at the top of the photocell definition) |
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1.1 | 9 | 11. Model can be "GLS-LDL", "GLS-LOL", "GLS-LCL", or "GLS-LEXT" for non-system sensors |
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2.1 | 10 | 11. HostDevice should be the model name in quotes for the device the photocell is wired to (GLS-SIM, ZUMLINK-JBOX-16A-LV, ZUMNET-JBOX-16A-LV, etc.) |
| 11 | 11. HostPort will be "1" without quotes for most devices. Exceptions are: | ||
| 12 | 111. GLS-SIM or C2N-CBD-P where the photocell is connected to port 2 will be "2" without ports | ||
| 13 | 111. GLPAC will correspond to the number of the dedicated photocell port that the photocell is connected to (1-4) | ||
| 14 | 11. DeviceHostId is the IP-ID in quotes for the host device or "null" without quotes if connected to a device without an IP-ID (e.g. a GLS-SIM connected directly to the processor) | ||
| 15 | 11. DevicehostBranch is "1" without quotes for most devices, with the exception being devices on DIN-CENCN-2 net 2 where the DeviceHostBranch will be "2" without quotes | ||
| 16 | 11. DeviceConnectionId will be the hexadecimal CID (Cresnet ID) of the host device in quotes | ||
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1.1 | 17 | 1. Verify the photocell is connected to the correct device (compare serial numbers to ensure the IP-ID, CID, and model match of the host device matches the configuration) |
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2.1 | 18 | 1. Verify wiring at the host device: |
| 19 | 11. For ZUMNET/ZUMLINK-JBOX the photocell should be using ports 4, 5, and 6 on the green terminal block, corresponding to 24V (red at the photocell), signal (orange at the photocell), and ground (black at the photocell) | ||
| 20 | 11. For GLS-SIM, there are two ports with two dipswitches each: | ||
| 21 | 111. Dip switches 1 and 2 correspond to port 1 while switches 3 and 4 correspond to port 2 | ||
| 22 | 111. Dip switches are all in the on (up) position from factory, but photocells should have the dip switches for their port set to on-off (up-down) | ||
| 23 | 1. Verify signal/power at the host device: | ||
| 24 | 11. Verify the host device is outputting 24V on the correct port | ||
| 25 | 11. Verify you are receiving a 0-10V signal at the host device by disconnecting the signal wire and measuring its voltage to ground | ||
| 26 | 111. You should see a sensor reading between 10V and 0V, with 0V being the reading when it is covered up. Ideally a second person will be at the photocell to shine a light or cover it up to verify readings are changing | ||
| 27 | 11. If there is no 24V output, then the host device is probably faulty and you should contact Crestron for troubleshooting or replacement | ||
| 28 | 11. If there is no 0-10V signal, proceed to troubleshooting at the sensor | ||
| 29 | 1. Verify signal/power at the sensor: | ||
| 30 | 11. Verify 24V is reaching the photocell by disconnecting the photocell's red wire and measuring voltage on the cable from the host device | ||
| 31 | 11. Verify the photocell is outputting a 0-10V signal by disconnecting the orange wire and measuring voltage on the orange wire | ||
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1.1 | 32 | 11. If you get a reading at the photocell but not at the JBOX then there is likely a wiring issue, i.e. wrong cable connected or the cable is damaged in the field |
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2.1 | 33 | 1. Check the jumpers/switch at the photocell to make sure the reading is in the correct range: |
| 34 | 11. Open loop 3-300fc (default) | ||
| 35 | 11. Open loop 30-3000fc (bright windows) | ||
| 36 | 11. Open loop 60-6000fc (skylight/exterior application) | ||
| 37 | 11. Closed loop 3-300fc (downward facing photocell) | ||
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| 39 | = Inverted Reading in ShowRunnerCLC™ = | ||
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| 41 | Inverted readings in ShowRunnerCLC™ are usually the result of incorrect dip switches at the host device such as a GLS-SIM. This can be corrected without physical access to the host device by changing the Invert property in the config from false to true | ||
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| 43 | 1. k the jumpers/switch at the photocell to make sure the reading is in the correct range: | ||
| 44 | 11. Open loop 3-300fc (default) | ||
| 45 | 11. Open loop 30-3000fc (bright windows) | ||
| 46 | 11. Open loop 60-6000fc (skylight/exterior application) | ||
| 47 | 11. Closed loop 3-300fc (downward facing photocell) | ||
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