Keypad flashing when pressed

Hi,
I have an issue whereby the keypads will flash blue/orange and not work but if I press it again for second or third time it will work.

At first I thought it was a power supply issue, stupidly I didn't test the voltage at multiple points only at one point this was 22v

I thought it was a power issue so I added a spare module with power to the system which seemed to settle it down but a day later it started happening again.

I ran a diagnostic and it showed some KP had 16v but others are 22v but I ran the diagnostic again and it showed all KP over 22v

The bus power come from the modules and doesn't have a separate PSU.

All modules with power have been tested individually and show 36v.

As it's a fairly large system in a residential property it's not that easy to fault find.

If anyone can help with a better way to fault find it will be greatly as appreciated.

The system comprises

50 x dlt/4 button Saturn
12 x 4/8 channel dimers
5 x 8 channel relays
3 x 0-10v
16 shutter relays
1 X5500PC

Thanks

 

This is a pretty common problem. The dimmers and relays that have power supplies can cause 'noise' on the bus. Even though they are operational, the power supply can be faulty/noisy and corrupt the bus signals.

You might need to try unplugging each dimmer and relay unit (one at a time) from the bus and see if the problem goes away. Best also to use an analogue multi-meter to check the voltage and not rely on the internal measurement at units. I have a purpose built box that includes an analogue meter to measure voltage along with a power supply (that I can switch in and out) and a bunch of resistors that load the bus. The resistors can cause a power supply that is marginal to fall over.
Also, look for flashing/flickering on the C-Bus indicator on a relay or dimmer unit. This may indicate a problematic power supply.

 

Hi,

we are based in sheffield and would be happy to come over and have a look, this kind of problem isnt always a quick fix.

 

Highly recommend Ben Addison for anything to do with C-Bus in your part of the world.

 

If your checking the cbus voltage you need to check across the plus snd minus AND also both the plus and minus to ground, this must be balanced,, eg 4.5v on both lines if not it indicates a bad power supply