Wiring HF Flourescent Lights

Joined
19 Aug 2007
Messages
17
Reaction score
0
Location
London
Country
United Kingdom
I am trying to wire a simple set up of two 6ft 70w high frequency twin tube fluorescent lights to be plugged in at a wall socket. These are the type with an electronic ballast/ no starter. I wired the mains cable to the terminal block of the 1st light and then a cable from the same terminal block to the second light. The second light worked fine, however the 1st light cuts out after 30-60 seconds. Afterwards, I tried the 1st light alone but it still goes out after 30-60seconds. I have tried changing the lamps.

Is it likely that I have a faulty unit? Could the wiring configuration I used have damaged the ballast? What is the correct way to wire two HF lights from the same power cable? Any help appreciated, Thanks.
 
Sponsored Links
Joined
19 Aug 2007
Messages
17
Reaction score
0
Location
London
Country
United Kingdom
Thanks. Sorry I am not an electrician. I understand Live goes to Live, Neutral to Neutral, Earth to Earth, but could you explain the loop in more detail please?
 
Sponsored Links
Joined
19 Aug 2007
Messages
17
Reaction score
0
Location
London
Country
United Kingdom
The lights do not have a separate block for a loop, only one terminal. I had the the L, N, E for the power cable wired to the terminal block in the 1st light and the L, N, E of a cable leading to the 2nd light twisted together with the L, N, E wires leading out on the opposite side of the terminal block on the 1st light. Was this correct? Thanks.
 
Joined
15 Apr 2005
Messages
16,502
Reaction score
264
Location
Yorkshire
Country
United Kingdom
The lights do not have a separate block for a loop, only one terminal. I had the the L, N, E for the power cable wired to the terminal block in the 1st light and the L, N, E of a cable leading to the 2nd light twisted together with the L, N, E wires leading out on the opposite side of the terminal block on the 1st light. Was this correct? Thanks.
FOR THE 3RD AND FINAL TIME

yes. You wired them correctly. I dont know what other way you think you could have wired them.
 
Joined
19 Aug 2007
Messages
17
Reaction score
0
Location
London
Country
United Kingdom
Well. It wasn't a faulty unit. I replaced it with a new unit. It worked fine for the first couple of tries, then the same fault occurred: lamps cut out after 30-60 seconds. Wired up as described above, so I've no idea why. Any ideas?
 
Joined
28 Apr 2004
Messages
6,377
Reaction score
449
Country
United Kingdom
I spend a lot of time renewing HF fittings in a local school, quite often a tube will strike up for a short period and then go off when the ballast is faulty
 
Joined
17 Mar 2011
Messages
68
Reaction score
1
Country
United Kingdom
I spend a lot of time renewing HF fittings in a local school, quite often a tube will strike up for a short period and then go off when the ballast is faulty

do you know if a 35W HE fitting is comparable 'light output' to an older T8 58watt w/magnetic ballast
 
Joined
3 Nov 2006
Messages
27,155
Reaction score
2,954
Location
Bedfordshire
Country
United Kingdom
Can you try the units one at a time to see if they work when only one is connected to the plug ?

It might be that the ballasts are taking power from the mains in very short but high current pulses from the mains and this is causing local voltage fluctuations ( on the cable from plug to lamps ). The voltage fluctuations caused by one ballast then disrupting the working of the other ballast and vice versa.

Sometimes this is "cured" by a capacitor across Live and Neutral, often mis-named as a power factor correction. If the lamps do work reliably one at a time then contact the supplier / manufacturer for their advice / recommendation as to how to prevernt this inter-action between ballasts.

On ordinary flourescents it is a power factor correction device, but on "rogue" high frequency ballasts it is a suppressor device.
 

DIYnot Local

Staff member

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.


Are you a trade or supplier? You can create your listing free at DIYnot Local

 
Sponsored Links
Top