Solar PV "Power failure"? Technicians in North East? Help!

victor2

Telegraph_Sam said:

What you say is correct. I'm still only half way through learning what the jargon means ..

Latest plan is to purchase what looks like an identical MCB from eBay, and simultaneously establish contingency contact with a suitable electrician with the aim of being able to react quickly in the event of another power failure.

Good luck with that. Unless you have a mate who is an electrician, it's not going to happen. Much better to find a local qualified electrician, tell him what you need and let him supply and fit it.

Heedtheadvice

As per victor2.

Just get an electrician.

They could already have a suitable MCB (Those ones are very common) in stock or will get one at local supplier off the shelf.

Ebay has a variety of sellers and not all sell quality products. It has not just to look right it has to have the correct spec. It also has to be fitted safely and in accordance with the British Standard.

MCBs are not binary. They react to current and duration of overload. You need one with the correct spec.

Given you experience with it and the fast change it will take to fit a new one ( as has ready been mentioned by another poster ) just bite the bullet and know you have a good one fitted.

As also mentioned you do not need an RCBO, and that will take a few more minutes to fit and cost a bit more probably....

Put you effort into finding a local electrician. There are many in your area even showing on Google maps. A close smaller business that does domestic work might be in a better position to respond.

paul991

buy a spare , looking at a few pounds then ready if it happens again. 

Netexporter

I'd consider getting a whole new 18th Edition consumer unit. That would have surge protection, which will offer further protection for the inverter and get one with a couple of spare ways so you can easily add batteries and an EV charger at a later date.

Telegraph_Sam

As things stand I have a replacement RCB and MCB (I have probably got the terms mixed up) waiting for an electrician to come and fit them.  The situation was that it was impossible to stop one or other of the units tripping immediately. The latest is that I have been able to re-set the units on a temporary basis but it looks like the MCB trips when the power comes on in the morning.

Taking Netexporter's point, the consumer unit was replaced a few years ago so it is not that ancient. I can see on it if a circuit has caused the protection to trip, and re-set it. But this seems to operate independently of the RCB and MCB and has obviously not stopped either from tripping as I have been describing.

Question: With the various changes, does the energy downloaded per hour depend on the strength of the sunlight at any given time of the day? Or is it a binary situation - you either get your kW's or you don't depending on whether the wee green light on the inverter is illuminated? [I now realize that the answer might be contained in HeedTheAdvice's advice 3 posts ago.]

Can one in fact measure the efficiency of the installation, and if it fails to meet a spec then take corrective action? I asked my original installer this recently but did not get a clear answer.

QrizB

Telegraph_Sam said:

As things stand I have a replacement RCB and MCB (I have probably got the terms mixed up) waiting for an electrician to come and fit them.

I'm glad that you've got things in hand, although you've been having problems for a month now - a month of reduced generation and fewer earnings.

Telegraph_Sam said:

.The situation was that it was impossible to stop one or other of the units tripping immediately.

It sounds like something is causing a phase-to-earth fault. Your electrician should be able to identify what.

Telegraph_Sam said:

Question: With the various changes, does the energy downloaded per hour depend on the strength of the sunlight at any given time of the day? 

The power output depends on several things, but the main ones are:

- the incident angle of sunlight onto the panels 

- and cloud/shade/dust/smoke/volcanoes etc. between the sun and the panels 

Typically, on a clear day, the panels will turn the inverter on around sunrise (when light first falls on them) at a very low output. The output will rise to a peak somewhere around midday and then fall back again in the afternoon, finally switching off again around sunset.

For my panels it's something like this:

Yours will be similar but not identical.

Telegraph_Sam said:

Can one in fact measure the efficiency of the installation, and if it fails to meet a spec then take corrective action? I asked my original installer this recently but did not get a clear answer.

The easiest way is to compare the monthly/quarterly/annual output from your system to the prediction that your installer supplied when they installed it.

Slightly more complicated is to model your system in a tool like PVGIS and compare your actual output to that.

Less accurate, you can compare your system to itself year by year (if you have the records) or to other people's systems.

Telegraph_Sam

The two units RCB and MCB are awaiting a visit from the electrician meanwhile the trip has actuated such that the circuit is more off than on. I must mention the phase-to-earth suggestion when the man cometh. A thought I had was that perhaps the MCB is in fact doing its job properly and that the fault could be elsewhere

QrizB

Your electrician should investigate and fault-find before replacing anything. If they don't, you need a better electrician!

Telegraph_Sam

I just need to mention phase-to-earth for him to take me seriously ..
A purely academic point, what would the risk be if I was to tape over the MCB in its live position? The fuse in the consumer unit would still be my main protection.

QrizB

Telegraph_Sam said:

I just need to mention phase-to-earth for him to take me seriously ..
A purely academic point, what would the risk be if I was to tape over the MCB in its live position? The fuse in the consumer unit would still be my main protection.

Well, there's a small chance your house will burn down ...
but an MCB should be designed to trip even if the lever is somehow held in place.