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Can you post up a photo of what you have at the moment both sides of the boards, that will give me some idea where you are at, in the mean time are you using stripboard?

I have to say that despite the few components in a Mk2 it is not a beginners project due to it involving mains voltage safety is the prime concern.

Many thanks for the reply.

I have attached 3 photos of the project, but can supply more if you require them. Don't know if it helps but if I load Tallymode the triac don't come on until I run the programme, but will not then go off or flicker until I switch off.

I am reasonably comfortable with mains voltage and all the testing has been done through an RCD, but I appreciate the warning. Many thanks.

Hi, have you followed the suggested sequence of activities in Section 8 of my online article about diverting surplus PV? 

If your sensors are not giving sensible values, then your system clearly won't work.  Getting the sensors right is always the first thing to do.  The first few tools on my Summary Page should help with this (if you want to post any results, please try to reduce their bulk, there's no need to post great long lists of numbers!)

There are three parts to a Mk2 Router system: the measurement side, the energy bucket, and the power diversion side.  Once you've got the input sensors (i.e. the measurement side) to behave as expected, the energy bucket's level should respond accordingly.  This can be verified by using Mk2_PV_Router_mini_3 which displays the amount by which the energy level has changed each second.  So if you're measuring the current that's being taken by a 60W bulb, the string of numbers should all read "60" or thereabouts.  If they don't, just adjust your powerCal value until they do.  Your system is then correctly calibrated.  That same value of powerCal can be used in any other Mk2 version and your system will always be correctly calibrated (unless you change the hardware)

Although potentially dangerous, getting the output side to work correctly is very straightforward.  90% of the problems are with people's voltage and current sensors not being set up correctly.

Disconnect the mains feed, just power the arduino for now

You need 2.5v on the op amp output  - pin 1. you should also have 2.5v on pin 3, 5v on pin 8 and 0v on pin 4

Try disconnecting the white wire to the jack socket and see if the voltages are then sensible. If not it looks like the op amp is dead.

Bob

Just seen that Robin is online - he's the boss on this one!!

I'll bet you ten-to-one that the op-amp isn't dead!

I'm no expert on these things.  It's just that having probably removed at least ten suspect op amps over the years, they've always been OK.  It's always something else that I've done wrong!

I honestly don't intend this as a plug, but my circuit boards are only £10 and ensure correct wiring at both ends leaving minimal room for error, if you are interested.

Start looking for the thing that is so simple and obvious that it can't possibly be wrong.

Or send me a PM if you really feel that you're getting nowhere! 

There's nothing like solving problems yourself, albeit with a bit of assistance, to boost the confidence.  What you've built so far looks fine to me ...

Thanks everbody.

I think I may have solved the problem. I ordered an Arduino power supply and when it arrived it was 9 volt 1 amp. It ran the Arduino fine. My wife was reading one of the posts regarding not powering the Arduino from a USB supply as under load it may give less than the required 5 volts and cause the  op amp to shut down and asked if that could be the problem . I found a 12 volt 0.5 amp supply with the right plug and powered it up. Lo and behold 2.5 volts as required.

You live and learn.

Once again thanks for all the help.

The worrying question here is, which one of the following is correct:

1. Something is drawing far too much current and causing your 9 V 1 A power supply to drop it's voltage, presumably because it is overloaded.
2. Your 9 V power supply is not capable of giving the rated current.

I think you need to investigate this, if only to learn what and why. Power supplies are normally rated to give the nominal voltage at the rated current, and usually give a higher voltage when lightly loaded. For example the recommended a.c. adapter is rated 9 V,  6VA, which equates to 666 mA. The way we use it, it has almost zero load and the voltage is around 11 V.

The second lesson - which should have been the first one - always check your incoming voltages first.

Glad to hear it's sorted, as I've said not all PSU are the same or as capable. As Robert said look for what can't possibly be wrong.

Just got my first tank of, very hot, solar heated water today.

Everything seems to be working fine now, thanks to your and Robins help.  However if I use the old 9 volt power supply the Arduino works but nothing else does. That supply seems to be working OK and is giving 9.14 volts and I have checked the pin output polarity and it appears OK ???????.

After I got it working I check the voltage and current sensors using Robins Rawsamples and several other tools and found that the CT was giving quite low readings. After some advice from Robin on burden resistors, I removed the resistor from the CT (quite easy) and substituted a 150 ohms on the circuit board. This gave much improved readings on all the sketches.

Once again thanks for all the help.