Adrian H
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I've recently replaced two long tube fluorescent lights with LED lights.
I did this in two stages, where for a short while only one fluorescent unit was replaced by LEDs and one old tube was still in the circuit.
All was well.
Once I replaced the second tube the phantom voltage became evident. The LEDs are still on, be it dimmer, when they are switched off. Sometimes you have to turn them on to realise they were off before - it can be that bright sometimes, though usually obviously much dimmer.
I'm not aware of any floating earths or neutrals in the circuit but have not conducted any specific tests for this. I do have a AstroAI DM6000AR digital multimeter if its of any use in this situation.
I'm confident the pair of two-way switches are wired OK (not changed anything there, just checked the wiring) , and I'm confident the first light I replaced with the loop-in wiring (see attachment) is wired correctly.
It seems there is a phantom voltage induced in the wiring - or capacitance effect.
What I also know is each fluorescent lighting unit had a 5.5uF 250VAC capacitor connected across live and neutral that is now removed from the circuit. I've learned a capacitor connected this way can solve ghost voltage issues. I kept one of these capacitors, so I could add it back into the circuit, but I'm not confident it is the right value for the situation or the right thing to do - masking a problem that needs solving another way?
The combination of all the new LED lights will be drawing around 0.6A (2x18W + 3x36W).
I could try to measure the phantom voltage and current with the multimeter if it provides meaningful information.
Note switching off the lighting circuit at the consumer unit with the circuit breaker switch does make the lights go dark.
Any advice on my next step?
I did this in two stages, where for a short while only one fluorescent unit was replaced by LEDs and one old tube was still in the circuit.
All was well.
Once I replaced the second tube the phantom voltage became evident. The LEDs are still on, be it dimmer, when they are switched off. Sometimes you have to turn them on to realise they were off before - it can be that bright sometimes, though usually obviously much dimmer.
I'm not aware of any floating earths or neutrals in the circuit but have not conducted any specific tests for this. I do have a AstroAI DM6000AR digital multimeter if its of any use in this situation.
I'm confident the pair of two-way switches are wired OK (not changed anything there, just checked the wiring) , and I'm confident the first light I replaced with the loop-in wiring (see attachment) is wired correctly.
It seems there is a phantom voltage induced in the wiring - or capacitance effect.
What I also know is each fluorescent lighting unit had a 5.5uF 250VAC capacitor connected across live and neutral that is now removed from the circuit. I've learned a capacitor connected this way can solve ghost voltage issues. I kept one of these capacitors, so I could add it back into the circuit, but I'm not confident it is the right value for the situation or the right thing to do - masking a problem that needs solving another way?
The combination of all the new LED lights will be drawing around 0.6A (2x18W + 3x36W).
I could try to measure the phantom voltage and current with the multimeter if it provides meaningful information.
Note switching off the lighting circuit at the consumer unit with the circuit breaker switch does make the lights go dark.
Any advice on my next step?
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