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Hi chaps,
Just wanted to gather some feedback about this topic. To give it some context, yesterday I went to sort out why one storage heater in a property was on all the time. 24 hour board + Economy 7 board.
History of the circuit... small bedroom had a convector heater removed and replaced with a socket outlet. At that time, the circuit was disconnected from the Eco 7 board and a piece of T+E was dropped through the bottom of the boards to link it to a 24 hour circuit.
Turns out, that same circuit supplied the storage heater. Nice simple fix. But testing... obviously off-peak board, can't do live testing as no supply. So this is the sequence of testing I did... can anyone think of anything that is wrong with this, or how can it be improved?
1. Dead test - R1+R2 - Verify continuity of line and CPC, had already verified during identifying the cicuit
2. Dead test - Polarity - This was confirmed by visual inspection and during identification of the circuit
3. Dead test - Insulation Resistance (all tests >999Mohm so the cable appears to be in very good shape)
3. Live test - Ze/Zdb - I verified Ze at the 24 hour board with earth disconnected, then reconnected and verified between earth bar in Eco 7 board and the line of the 24 hour board. Exact same figure
And that's it for testing. Zs will be Ze+(R1+R2) which is well within the limits of a 16A breaker at 0.58 ohm.
I've never given this topic a thought until yesterday so figured this may serve as useful info for others.
The only other thing about this circuit that got me thinking was the fact it is wired in 1.5mm T+E, not the 2.5mm (or equivalent) that I would expect to see for heaters. I know the cable I can see hasn't suffered any thermal damage, the storage heater that's connected isn't huge and I know that 1.5mm can handle this kind of power providing the installation method is correct, but is this usual?
Just wanted to gather some feedback about this topic. To give it some context, yesterday I went to sort out why one storage heater in a property was on all the time. 24 hour board + Economy 7 board.
History of the circuit... small bedroom had a convector heater removed and replaced with a socket outlet. At that time, the circuit was disconnected from the Eco 7 board and a piece of T+E was dropped through the bottom of the boards to link it to a 24 hour circuit.
Turns out, that same circuit supplied the storage heater. Nice simple fix. But testing... obviously off-peak board, can't do live testing as no supply. So this is the sequence of testing I did... can anyone think of anything that is wrong with this, or how can it be improved?
1. Dead test - R1+R2 - Verify continuity of line and CPC, had already verified during identifying the cicuit
2. Dead test - Polarity - This was confirmed by visual inspection and during identification of the circuit
3. Dead test - Insulation Resistance (all tests >999Mohm so the cable appears to be in very good shape)
3. Live test - Ze/Zdb - I verified Ze at the 24 hour board with earth disconnected, then reconnected and verified between earth bar in Eco 7 board and the line of the 24 hour board. Exact same figure
And that's it for testing. Zs will be Ze+(R1+R2) which is well within the limits of a 16A breaker at 0.58 ohm.
I've never given this topic a thought until yesterday so figured this may serve as useful info for others.
The only other thing about this circuit that got me thinking was the fact it is wired in 1.5mm T+E, not the 2.5mm (or equivalent) that I would expect to see for heaters. I know the cable I can see hasn't suffered any thermal damage, the storage heater that's connected isn't huge and I know that 1.5mm can handle this kind of power providing the installation method is correct, but is this usual?
