# Touching the lamps contacts

#### Lightingguy32

##### Active Member
IS it possible that the oil from our skin also can cause electricity to arc across the conctact pins of lamps and damage both the socket and the lamp from a short circuit, becuase 3 of our source four pars have fried sockets and lamps that have toasted contacts, from what is beleived to be caused by short circuited lamps due to people touching the lamps contacts

#### Foxinabox10

##### Active Member
As far as I know, arcing is caused solely by an improperly seated bulb in a fixture. Always make sure the bulb is down as far as possible before plugging it in. Also, whenever you change a bulb be sure to check for the arcing so that you don't ruin another bulb.

#### moderately_clueless

##### Member
Hmm, we have similar problem. We always assumed that the contacts were corroded. But the contacts on the fixturea nd the lamp were blackened. I'm not sure if you have the same problem, but it you're in a pinch, acetone or battery cleaner will make the fixture work for a few days before it gets all nasty again, otherwise, just buy a few replacement contact parts for the source fours, and you should be okay.

#### Footer

##### Senior Team
Senior Team
also you can get a retrofit kit that puts the retainer clip on older fixture that dont have one. I always have extra leads on hand for s4's.

#### Chris15

##### CBMod
CB Mods
Departed Member
Sweat is the major offender when touching things. Since sweats is salts and water, it could cause a small increase in the resistance of the connection which could lead to arcing. It also could promote corrosion and so this might be what is happening. Alternatively, the base has been subjected to arcing and so is creating problems for the connection. This can also cause the lamp to go bad. Ship has written on this in the past. Blackened pins are telltale evidence of arcing. Arcing is basically caused by electricity needing to jump an air gap to get to the bulb. It increases the resistance of the connection and this can get to the point where it will not conduct. Arcing can be studied in more detail in this previous question of the day thread on Hot Patching. The problem is the same, whether it be plug and socket or lamp and socket.

#### Lightingguy32

##### Active Member
We just send the fixutre sockets out for reapair every time this happens but next year when i am head of the "lighting" department in our schools tech club, i will specifically tell people NOT to touch the contacts, it is pretty much common knowledge that sweat is damaging any were on a lamp apart from the ceramic heat sink