# airport runway lights

#### muggins28

##### Member
I maintain an airport facility which includes regular maintenance of the runway and taxiway lighting. the problem is that half of the lights goes off occasionally can you list some of the problems and the solutions to the poblems

#### templdl

##### Senior Member
I maintain an airport facility which includes regular maintenance of the runway and taxiway lighting. the problem is that half of the lights goes off occasionally can you list some of the problems and the solutions to the poblems
A string of light, every other light? What do you mean a half of the lights? The facility should have a schematic/wiring diagram of the lighting shouldn't they?

#### jusme123

##### Senior Member
fly me out for a week I'll help you trouble shoot them :lol::lol:, its probable a loose connection

#### mgookin

##### Senior Member
I maintain an airport facility which includes regular maintenance of the runway and taxiway lighting. the problem is that half of the lights goes off occasionally can you list some of the problems and the solutions to the poblems
Is a breaker tripping and you have to reset it? Could just be an old breaker.

#### Rampage_Rick

##### Senior Member
Runway lights work on a constant current system and are wired in series (6.6A or 20A at up to 5kV) The reason for such a system is to make all the lights equally bright by eliminating voltage drop.

If half the lights are going out that would imply all those lights are on one circuit. The most likely cause would be an open circuit somewhere. Could also be a faulty constant current regulator (essentially a ballast)

#### muggins28

##### Member
runway lights

runway lights

A string of light, every other light? What do you mean a half of the lights? The facility should have a schematic/wiring diagram of the lighting shouldn't they?
yes it should but their isn't any. but theirs a string of lights of like 10 lights off the 2 on then 5 off, most times it is be the regulator or 1 of the light transformer. but the situation is that the runway is near the water and the high voltage lines and the transformers are basically in salt water all the time.

#### templdl

##### Senior Member
yes it should but their isn't any. but theirs a string of lights of like 10 lights off the 2 on then 5 off, most times it is be the regulator or 1 of the light transformer. but the situation is that the runway is near the water and the high voltage lines and the transformers are basically in salt water all the time.
This is how I would approach it.
Since the lights are essentially in a series circuit there must be an opening in that circuit. I would also assume that there is more than 1 cuit of lights such that if you loose 1 circuit as you have the 2nd circuit remains lit to assume that the runway still has enough markers lit is some fail.
Since the problem seems to be intermitant the problem may be difficult to problem shoot as the lights should be unlite to do so.since the actual distribution voltage is commonly very high as pointed out by one of the other posters using caution is imperative. I would look for a break between two of the lights or one of the lines at each end the strings open. But if this in intermittent it could be a pain to identify.

Last edited:

#### kwired

##### Electron manager
This is how I would approach it.
Since the lights are essentially in a series circuit there must be an opening in that circuit. I would also assume that there is more than 1 cuit of lights such that if you loose 1 circuit as you have the 2nd circuit remains lit to assume that the runway still has enough markers lit is some fail.
Since the problem seems to be intermitant the problem may be difficult to problem shoot as the lights should be unlite to do so.since the actual distribution voltage is commonly very high using caution
:? You started off with "this is how I would approach it". I was expecting something telling us how to troubleshoot, then all you mentioned is some info on how and why it is likely done the way it is. Any good ideas on how to find the open circuit point when it is intermittent like that, as well as taking consideration of the likely higher voltage? All I can think of that is somewhat simple anyway is to verify whether or not you are losing the supply or something in the loop when it does fail and then go from there. But if you need to troubleshoot the loop and the problem is intermittent, I can see this potentially taking some time to resolve.

#### GoldDigger

##### Moderator
Staff member
"Short circuit" a portion of the loop with an MOV in series with a small fuse. When the lights go out, check to see if the fuse is blown. If it is, the open circuit is in the part of the loop that you paralleled.
Maybe not practical, but a great theoretical solution.

Sent from my XT1080 using Tapatalk

#### kwired

##### Electron manager
"Short circuit" a portion of the loop with an MOV in series with a small fuse. When the lights go out, check to see if the fuse is blown. If it is, the open circuit is in the part of the loop that you paralleled.
Maybe not practical, but a great theoretical solution.

Sent from my XT1080 using Tapatalk
I can see some trouble with practicality, but I do like the logic. I guess a guy could start with installing one across each lamp, you may even find something suspicious at the offending lamp while doing that. This wouldn't help much if the problem is not at a lamp though, other than eliminate the lamps from the list of things to check. But I also suspect a bad conductor is not as likely to be an intermittent problem, a connection maybe, but eventually will probably completely fail.

#### GoldDigger

##### Moderator
Staff member
The other advantage of putting a "detector" at each light would be that you would, in the process, verify or remake each external connection at the lights.

Sent from my XT1080 using Tapatalk