I rarely encounter a volt drop problem and if I do it is usually because a installation is not being used as intended, such as a farm building being used as an industrial unit with a distribution circuit that was intended for a grain dryer or a few lights and sockets now being used for welders and other fabrication tools and equipment.

But what happens in reality is that fuses and trips open due to overload before the voltage drop is noticed to be an issue, when you’re on the phone trying to get a DNO fuse replaced on a pole voltage drop is not a real concern.


I do however have pads of EICR forms with a box to tick to say I have verified the voltage drops within the installation when I tested it.


In a small domestic installation you aren’t going to concern yourself about voltage drop, in a larger installation if a fixed appliance has sufficient voltage at its terminals when the appliance is under load are you really then going to start taking reference readings at the intake to work out the percentage drop in the circuit? Anyway as the voltage is possibly constantly changing due to loads altering and clouds in the sky affecting the output of the PV array on the roof how accurate can a figure derived from two two test results not taken simultaneously? How repeatable are loop test results?


The whole process of determining voltage drop by testing is very iffy, if this and if that, unless the tester applies a fixed load or simulates to make a virtually instant determination of what the voltage drop would be.


A simple little tick box on a certificate or report can really open you up to being quizzed as to what you did before you ticked it.


Andy 



 

I rarely encounter a volt drop problem and if I do it is usually because a installation is not being used as intended, such as a farm building being used as an industrial unit with a distribution circuit that was intended for a grain dryer or a few lights and sockets now being used for welders and other fabrication tools and equipment.

But what happens in reality is that fuses and trips open due to overload before the voltage drop is noticed to be an issue, when you’re on the phone trying to get a DNO fuse replaced on a pole voltage drop is not a real concern.


I do however have pads of EICR forms with a box to tick to say I have verified the voltage drops within the installation when I tested it.


In a small domestic installation you aren’t going to concern yourself about voltage drop, in a larger installation if a fixed appliance has sufficient voltage at its terminals when the appliance is under load are you really then going to start taking reference readings at the intake to work out the percentage drop in the circuit? Anyway as the voltage is possibly constantly changing due to loads altering and clouds in the sky affecting the output of the PV array on the roof how accurate can a figure derived from two two test results not taken simultaneously? How repeatable are loop test results?


The whole process of determining voltage drop by testing is very iffy, if this and if that, unless the tester applies a fixed load or simulates to make a virtually instant determination of what the voltage drop would be.


A simple little tick box on a certificate or report can really open you up to being quizzed as to what you did before you ticked it.


Andy