Red Light on Digital Meter

[Nemo2000]

On my digital meter there is a red light, which normally is flashing at varying intervals. As I have always understood it, the situation is:-

1. No light = no incoming power (and yes, I've watched it for long enough to know that it is definitely off and not just flashing very slowly)
2. Steady light = incoming power, but no (or imperceptible) power being used in the house
3. Flashing light = incoming power, with power being used in the house.

Am I right, particularly with item ?

 

[EFLImpudence]

It just flashes when you are using power, the more you are using the faster it flashes.

It usually states on it the speed - e.g. 1,000 impulses per kilo Watt hour.

No flashes mean you are not using any power.

Obviously if there is no incoming power it will not be flashing either but that is incidental.

 

[EFLImpudence]

Ah - not sure about your number 2. You might be right.

 

[conny]

Have you checked to see if you have power by switching something on? e.g. tumble dryer, oven etc

 

[Nemo2000]

Yes, I do have power

To clarify, there is (hopefully!) no problem with the meter, but I just wanted to clarify in particular what it means if there is NO red light showing at all. Does it mean that there is no incoming power available, or simply that none is being drawn?

 

[Colin Brenton]

No power available gives no LED at all.
Power available and being used gives a flashing LED.
Power available but none being drawn gives a solid red LED.

HTH

 

[JohnW2]

No power available gives no LED at all. .... Power available and being used gives a flashing LED.
Power available but none being drawn gives a solid red LED. ...

That's certainly essentially how mine works (but see **). In my case, there are two LEDs, one for kWh and one for kvarh. I've never seen the former one 'solid red' (except when the post-meter isolator has been open, but the kvarh one is sometimes 'solid red', particularly at night.

[ ** With mine, the 'solid red' LED does mean that literally NO power is being drawn - it means that the amount being drawn has fallen below the (very low) "creep threshold", such that accurate metering cannot be guaranteed (so it doesn't meter the usage at that level). ]

Of course, from the OP's point of view, "power available but only a very small amount being used" might result in the LED flashing so infrequently that he does not notice - so thinks that it is 'permanently off'.

Kind Regards, John

 

[Nemo2000]

No power available gives no LED at all.
Power available and being used gives a flashing LED.
Power available but none being drawn gives a solid red LED.

HTH

Which is what I have always understood to be the case.

The reason that I asked is because today we had a sudden loss of power in our house. Now the tails from the meter go to a RCD and the tails from that go to the Consumer Unit. The RCD had tripped off and refused to re-engage. Thinking that there might be a fault somewhere I turned off the main switch on the CU, but the RCD still refused to latch up and then I noticed that there was no red light on the meter, despite watching it for some while.

So I rang WPD to enquire about any power-cut, but was advised that none had been reported in the area. The call-handler took the view that it must be a fault in the house, but I explained that the CU was turned off yet the RCD still would not latch. When I explained that the red light was out, I was told that this meant merely that nothing in the house was drawing power (not surprising since the RCD was off!) and that it did NOT mean that there was no incoming power. This puzzled me....

During the course of the phone call the red light suddenly came on steady again, at which point I was then able to turn the RCD back on and it latched. I then turned the CU on and (fingers crossed!) since then everything has been OK.

Was the call-handler correct or not? The circumstances suggest not and that there had indeed a short outage - am I right or wrong???

 

[JohnW2]

... Was the call-handler correct or not? The circumstances suggest not and that there had indeed a short outage - am I right or wrong???

You could be right, BUT ...

When you say that the RCD "would not latch" until the red light on the meter came back on, do you mean that it's lever would not stay in the 'on' position when you pushed it up? If so, that would be the behaviour of what is called an 'active' RCD, which one certainly would not expect to find in that situation - one would expect a 'passive' one, which could be 'reset' (and would 'latch') whether or not power were available ... so there are still some 'uncertainties'.

Could you perhaps provide us with a photo of the RCD or, if not, tell us everything that is written one it?

Kind Regards, John

 

[Nemo2000]

....

When you say that the RCD "would not latch" until the red light on the meter came back on, do you mean that it's lever would not stay in the 'on' position when you pushed it up?......

Correct I will try to get a photo and post it here in due course, but may not be today....

 

[JohnW2]

Correct I will try to get a photo and post it here in due course, but may not be today....

Thanks.

Kind Regards, John

 

[Nemo2000]

Hope this helps...

Sorry about the poor resolution - low lighting and cheap old phone camera !

 

[JohnW2]

Hope this helps... Sorry about the poor resolution - low lighting and cheap old phone camera !

Oooooh!! I don't think that's an RCD - it looks like a truly ancient voltage-operated earth leakage breaker ("VOELCB") which should as been taken out of service many decades ago.

Kind Regards, John

 

[Nemo2000]

Oooooh!! I don't think that's an RCD - it looks like a truly ancient voltage-operated earth leakage breaker ("VOELCB") which should as been taken out of service many decades ago.

Kind Regards, John

You are quite right, I was being rather 'loose' with my terminology.

Actually, the VOELCB is a bit of 'sticking point' at the moment. It was installed long before our time here and still has the intact SWEB seal. No domestic electrician will get involved in changing it, saying that it was the responsibility of SWEB and hence now WDP. However WDP say that they only took over responsibility from SWEB up to and including the meter, but no further (agreeing that such 'intermediate devices' between the meter and the Consumer Unit are a bit of 'grey area'), so they will not change it either.

So we are having to keep our fingers crossed that it continues to function...not good

Any helpful suggestions welcomed !

 

[flameport]

Those devices don't require the presence of voltage to latch on. They don't trip when the voltage goes away either.
They can trip due to faults within the installation or in some cases outside of it.
They can also never trip, or trip once and never work again.

As above - should have been removed long ago. Obsolete since the 1980s.
May not even be required, depending on what the rest of the installation is like.