5753PEIRL light level pain

I am having some issues programming 5753PEIRL and a DSI dimmer. Sometimes it works and other times it does not.

The programming i have completed is as follows
On the 5753PEIRL
Movement set as ROOM 1 for both day and night move
Light level maintenance is set as ROOM 1 LEVEL

The DSI i have set the channel for ROOM 1 LEVEL and under the logic tab i have set AND ROOM 1.
I have also set the MIN ans MAX levels to 10 and 90%. And the Lux level 400 and 20% margin

Therefore i believe that when someone is in the room it should ramp to the set level. Some rooms do this others do not. They are all programmed the same.
One issue is when the room is dark the lights ramp to 100% and as soon as the room becomes bright it just turns off. No ramp down.

This is driving me batty

any help welcome

Super

 

The first problem I see is that your target level is probably set too high. The light level the unit sees is the light level on the ceiling, which is usually a lot lower than the light level on the desks below. If your goal is to have 400 lux on the desks below then you're going to need a light meter on the desk and then adjust the target value in the sensor accordingly. Depending upon the office, it will probably wind up being about 150 lux or so.

The second problem is most likely that your margin is way too wide. Again, with small changes in level on the ceiling you'll see bigger changes on the desk below. Until you've got the behaviour fully sorted, I'd set the margin down to the minimum and then open it up to a few percent once everything is working.

The PIR will issue an On command against the RROM 1 group, which will turn it on. Because the light has been off, the ROOM 1 LEVEL group will have been ramped up to maximum in the background by the light level maintenance feature, as it tries to maintain the light level at 400 lux, but the light level isn't increasing since the PIR has turned the ROOM 1 group address off. As a result, the ROOM 1 LEVEL group will slowly ramp up to maximum whilst the room is unoccupied. Because of this you can typically expect the room to turn on at full brightness when the PIR detects motion.

The variability you've been seeing in "sometimes works, sometimes doesn't" probably relates to how long you've been waiting between tests, and what level the ROOM 1 LEVEL group is currently at.

If you're in any doubts, the best thing is to connect to C-Bus using the Diagnostic Utility to monitor the C-Bus traffic so that you can see the levels of the groups.