Electrical transient suppression

[benleeys]

Hi guys,

I am hoping that the electrical experts amongst us might have some advice for me.

The power switch for lowering and lifting my electric movie screen apparently causes a power surge whenever activated. When audio/video system is playing, the surge causes it to mute for a few seconds. Exactly which particular item is affected, I cannot say. For whatever it's worth, I have 2 RGPCs in my system, but they do not appear to be effective in this instance. Short of calling in the electrician, is there a simple solution to this problem?

 

[enilsen]

I would try hooking the electric movie screen to a separate circuit in the house and see if it makes a difference. The load on the current (common) circuit might be close to it maximum rated load when you activate the screen.

In some cases there could be a flaw with the house fuse pending on what type of fuses you have. I've personally experienced hot fuses when in use due to not being secured properly.

 

[benleeys]

I would try hooking the electric movie screen to a separate circuit in the house and see if it makes a difference. The load on the current (common) circuit might be close to it maximum rated load when you activate the screen.

In some cases there could be a flaw with the house fuse pending on what type of fuses you have. I've personally experienced hot fuses when in use due to not being secured properly.

Enilsen,

Thanks for responding. The electric screen is on a different circuit from the system which uses two dedicated circuits, both on a separate ELCB from lighting and other power circuits in the house. The fuses at the supply box are those circuit breaker type which trip when there's an overload.

 

[twich54]

Ben, It could be in the switch but I suspect the motor that operates the screen. Problem with commutator, armature, brushes , etc that's creating the excessive current draw. Is it a momentary type of switch ?? I'm assuming it's not a low voltage motor operating off a wall wart, so it has the same draw characteristics of a compressor (fridge, freezer,Ac) upon start-up.

 

[benleeys]

Ben, It could be in the switch but I suspect the motor that operates the screen. Problem with commutator, armature, brushes , etc that's creating the excessive current draw. Is it a momentary type of switch ?? I'm assuming it's not a low voltage motor operating off a wall wart, so it has the same draw characteristics of a compressor (fridge, freezer,Ac) upon start-up.

No, Dave, it's not the momentary type. It's a 3-pole switch - press one way, the screen goes up, press the other and the screen comes down. The switch is connected directly to the supply, ie it's a mains switch. You think it's a DC motor working off an AC-DC converter all packaged inside the screen housing? Would a couple of capacitors across the switch terminals cure the problem?