Troubles with relay unit 5512RVF

Hello!

There are troubles with relay unit 5512RVF. When I try to switch on the channels with buttons on the front side of the unit (local toggle, not c-bus command), all the channels switch off automatically after 3-10 seconds (ie rather quick). Power reconnecting of the unit doesn't help. There are no c-bus cables connected to this unit, only power and loads. The unit has been programmed and worked well until this issue. It has inbuilt power supply, c-bus clock and burden activated on it (unit address 1). Though no c-bus is connected, C-Bus led is on constantly (not flashing). What should I do to help the unit work properly? May be overload? Is there any overload thermal sensor in such units?

Looking for replies and questions if any.

 

There is no thermal sensor in the 5512RVF that would explain your unit's behaviour.
It is possible that one of the local toggle buttons is sticking, due to interference with the enclosure or ingress of dirt. If any button is held for longer than about 400ms, the local toggle will be cleared, which could explain your observations.

If that's not it, perhaps more information might help.
Does the unit work normally when controlled from C-Bus?
Has the unit been exposed to moisture?
Is it possible that insects have made their home inside the unit?
what is the firmware version of the unit?

 

Hello!

A little bit more info.
Sticking buttons are not the cause, there are some more such units, which are controlled the same way. The others are fine.
The complete c-bus installation is not finished right now, so its hard to check the c-bus control, light is switched locally. PIR sensors control relay channels well, until the relay unit itself works well.
The place of installation (switchboard, DIN-rails, all the channels are protected with MCBs) should be comfortable enough for the units, no insects or moisture there.
Firmware of the units is "1.6.00".

New annoying thing. Test installation consists of two relays 5512RVF, 5500PAC (absolutely empty), 5500NB (no far side connection surely), three PIRs 5751 (distantly from the swithboard). C-bus power is more than enough. During operation the Unit and C-Bus leds on one unit are flashing very rarely (sporadically) but simultaneuosly. All the other time they both are on constantly. So the questions: why c-bus led flashes sporadically? why unit led is on almost every time though the unit is in override mode?

More about the behavior of the buttons. I softly press one button, the second one, third, etc, 9th (for example). 9th channel is not switching on (like the unit got stuck) and right after that all the channels are off quickly. This happens even if all the channels' load is switched off through MCBs. Hope this helps to determine whats wrong.

 

I sounds to me like the units aren't getting sufficient mains voltage for reliable operation. The units should work over a supply voltage range from 192 to 264V rms if they have a nominal rating of 240V (-20%, +10%).
There is an unregulated internal voltage rail derived from mains. If this voltage is below a limit ( I can't recall the range of this limit, but it should be well below the normal operation of units), then the internal microcontroller goes into a special mode where it turns off every LED and attempts to store the current operating state in non-volatile memory. After storage is complete, the unit will attempt a power-up reset.
What is the voltage measured across the A and N terminals?
What is the nominal voltage rating of the unit (from label.. we make a few variants for different countries)?

 

Thank you for help, Don.

The exact type of the units is L5512RVF (ie 220-240 V). I will check mains supplied and post the results soon.

 

The voltage is approx 215..217 V, should be OK.
But there is one more issue. When the local button of the particular channel (not everyone) pressed, both the Unit and C-Bus leds go off for less then a second simultaneuosly (fraction of a second, can't say exactly). The channel goes on. After that any other button is unavailable (the press does nothing), pressed channel goes off after a second (approx). The mains during this test is fine accordingly to the simple multimeter. The channel is without any load (swithed off by MCB). I will try to view the mains with the oscilloscope. So what anyone can say?

 

I have duplicated conditions with a good unit here and don't see any problem, but if I drop the mains input voltage to about 180V, I can see the same symptoms that you are seeing.

It is possible that there may be a small batch of units that have problems at 217V. While customers in Australia (240V mains) would not notice the issue, you are having troubles.

The products are rated to operate from 220V to 240V, and as I have stated earlier, we try to ensure that they will operate over a wider range (192 to 264). Unfortunately it looks like your conditions are just out of range.

You should return the unit for a replacement, preferably from a different production batch (I'm not sure if there is a date code you can refer to)

If you can't arrange a suitable replacement, you could provide something to boost the voltage supplied to the unit.