PIR Lamp advice request.

[CARROT]

Anyone any ideas please? I have tried to replace a non PIR lamp with one with an integral PIR. The original had both reds connected to a terminal block - one black wire to the neutral terminal of the plain lamp and another black to the live terminal - so I placed a piece of tape on it for future identification. The earth's were obvious.
I have tried to connect up the new lamp - with the flagged black wire to the live terminal, the plain black to the neutral and the earths connected together - the reds remaining in the terminal block playing no part of the connection to the PIR unit and lamp. When power is connected the PIR seems to trigger but the lamp doesn't light up - I have checked that the bulb works.
Any ideas if I have done something wrong or could the unit be at fault?
(no MCBs tripped when I powered up)

 

[JohnD]

Just to check, you have got the installation instructions with your new lamp, haven't you?

What is it supposed to do when you have connected it, but it is not yet dark outside?

Have you tested the various wires to see which are live and which are neutral? Do some of the wires go to a switch inside?

 

[CARROT]

Many thanks for replying. I have checked the instructions and all seems well re installation although I haven't checked the identities of the black wires - perhaps I should change them around. Any idea why the PIR is triggering if the wires are around the wrong way?
The commission sequence is set the Lux to the sunny extreme and the time to the least setting, power up and within 60 secs the light should come on for 30 secs. As yet nothing.

 

[securespark]

You have made certain the nipples on the lampholder contacts are in contact with the dimples of the lamp?

 

[CARROT]

Sadly the bulb fitting for a Standard Edison Screw bulb and not a bayonet fitting.

 

[JohnD]

No nipples and no dimples

 

[kevnurse]

Hi, How do you know the PIR is triggering? Also, do you have the means to determine which of the 2 black wires is the switched live wire, ignoring the fact that one of them was connected to the live terminal. They could have been wrongly wired when the original lamp was fitted.

 

[CARROT]

I believe PIR is triggering because I can hear it click as if it is switching when I walk across the beam catchment area. It then clicks again a short time later as if it is switching off.

I am going to test the two black wires by terminating them in chocolate box terminals, then I will switch the power back on and then use a mains testing screwdriver to establish if the so called live is what it purports to be etc. Like you I have my suspicions that the person who wired the original non PIR lamp wired it to work rather than wired it faithfully to the nature of the wires.

Please advise if you think I should try any other methods to test the nature of my two black wires.

 

[JohnD]

I definitely think you should buy a multimeter and test across all of the wires. It is quite common for an induced voltage to arise in wires going to a switch, this is too slight to operate a bulb but will often cause flickering on a CFL and might be enough to operate your PIR electronics but not the lamp. This kind of voltage may appear on a test screwdriver (which is very inaccurate and unreliable) but will disappear under load.

 

[Spark123]

Can you check the lamp with a multimeter? As you can hear the click I would be tempted to look at the lamp/lampholder/fitting part first. Some ES lampholders are a bit rubbish in they have a centre contact and an offset contact which can have a tendancy to bend back creating a bad contact. Then there's the possibility of a loose contact inside the fitting. Don't do too much though if its under guarentee!!

 

[CARROT]

Okay - will go and get the multimeter - I appreciate that I am going to sound dense here but I am assuming I put one probe on the Earth terminal and one on another wire ie measure the potential difference (voltage). If I am not on the correct track please advise.

 

[JohnD]

One on Neutral, one on Phase for a start. Test each of the 4 wires to each of the others. Test to the Earth last (it may trip the RCD but will do no harm).

 

[Spark123]

You need it set to volts AC on a range exceeding 240v.

 

[Slumberland]

230 volts..

 

[ltheb]

230 volts..

That was pointless!