Since there seems to be some knowledgeable sparkies on this forum I'll ask what might be a dumb question:

A friend brought a 240 V / 60 Hz timer back from the states and I'm a bit reluctant to use it here since we're on 50 Hz. Will it even work or will the different cycles affect the clock/burn it up?

If it is from the States it is most likely 110V 60Hz, so double check before you plug it in.

If it can be set to 220 or 240V (doesn't matter) or has an automatic voltage select (60-240 or so), depending on the design:

1) Everything will work just fine

2) The clock will be 16.7% slow

There are not many designs anymore using mechanical 60Hz for the clock, so unless it's an old mechanical clunker it'll be fine.

You can get an autotransformer to get 220 -> 110, but for something simple as a timer you're better off buying a cheap one here.

It's definitely a 240 V (heavy-duty use), 15 amp, 60 Hz, old-fashioned mechanical design. No battery back-up for the clock in case of a mains power failure (I'm using one of those right now).

I can live with the clock being a bit slow as I can re-set it each day because this timer would be turning on security lights outside. I just wanted to know if the different cycle would cause other problems...

Thanks

Well it will run slow definitely (a mechanical one probably won't have a 50/60Hz adjustment), the motor may overheat on 50Hz and cook itself.

Timers are so cheap here, why not just buy a cheapie

Sorry for being the skeptic here but I cannot imagine a normal, household residential type of clock used in the USA that uses 240 volts for power. You would not normally have a wall socket in a room wired for 220 volts in the US and if so it does not look like other 120 volt sockets and is not wired the same. Is this some specialized kind of clock? If so the power requirements would be similar to a electric dryer or electric cooking appliance and the plug/sockets required are different.

Sorry for being the skeptic here but I cannot imagine a normal, household residential type of clock used in the USA that uses 240 volts for power. You would not normally have a wall socket in a room wired for 220 volts in the US and if so it does not look like other 120 volt sockets and is not wired the same. Is this some specialized kind of clock? If so the power requirements would be similar to a electric dryer or electric cooking appliance and the plug/sockets required are different.

and even if this was the case US 240v and Thai 240v are two different animals. US 240v is two phases each 110/120v, Thai is single phase 220/240.

I agree but did not want to muddy the water even more.

Sorry for being the skeptic here but I cannot imagine a normal, household residential type of clock used in the USA that uses 240 volts for power. You would not normally have a wall socket in a room wired for 220 volts in the US and if so it does not look like other 120 volt sockets and is not wired the same. Is this some specialized kind of clock? If so the power requirements would be similar to a electric dryer or electric cooking appliance and the plug/sockets required are different.

and even if this was the case US 240v and Thai 240v are two different animals. US 240v is two phases each 110/120v, Thai is single phase 220/240.

Thai voltage is 220V 50Hz 2 wire for single phase applications, the Americans use single phase 3 wire supply with a centre tapped neutral, 115-0-115V 60Hz. 230V on the two outer wires. It is single phase in operation.

They also use 220/440V 60Hz this is a 3 phase system.

The timer motor would most likely overheat and burn out one can run a 50Hz motor on 60Hz but not the other way round.

They also use 220/440V 60Hz this is a 3 phase system.

220/440 is not a 3-phase voltage. 208Y/120 and 480Y/277 are examples of common US 3-phase systems. 120/240 is the prevailing single phase voltage for residential use in the US and the transformer has a center tapped grounded neutral.

They also use 220/440V 60Hz this is a 3 phase system.

220/440 is not a 3-phase voltage. 208Y/120 and 480Y/277 are examples of common US 3-phase systems. 120/240 is the prevailing single phase voltage for residential use in the US and the transformer has a center tapped grounded neutral.

At last....a correct answer about American voltages etc

They also use 220/440V 60Hz this is a 3 phase system.

220/440 is not a 3-phase voltage. 208Y/120 and 480Y/277 are examples of common US 3-phase systems. 120/240 is the prevailing single phase voltage for residential use in the US and the transformer has a center tapped grounded neutral.

One was refering to multi voltage motors 3 phase 60HZ 208/220/440V in this case

Just get a light sensitive switch since it is for securety-lights, and this discussion about voltage and frequency is over.

Where was there any mention of controlling security lights? What have I missed?

Where was there any mention of controlling security lights? What have I missed?

Post #3

Thanks Crossy,,,,,the old eyes just aren't what they used to be. That changes one of my replies about it being a plug in type of timer as this most likely was hardwired in and could very well be a 220V 60Hz device. But I think we all agree this unit will not be suitable here

They also use 220/440V 60Hz this is a 3 phase system.

220/440 is not a 3-phase voltage. 208Y/120 and 480Y/277 are examples of common US 3-phase systems. 120/240 is the prevailing single phase voltage for residential use in the US and the transformer has a center tapped grounded neutral.

One was refering to multi voltage motors 3 phase 60HZ 208/220/440V in this case

Most 3-phase motors sold today in the US are rated for 208-230/460 or 230/460 volts. 220/440 volts applied to a 3-phase motor would be outside the recommended voltage drop limits for feeders and branch circuits of the National Electric Code (NEC) for the standard 480Y/277 volt industrial service.