Man i hate these Harbor Freight/ Hydrofarm digital timers

[NirvanaMesa]

Not much can go wrong with them besides an arc, and if that does happen, you'll know about it.

If you are starting a big load, the load should be run through a contactor switch used for well pumps. This will take the contact arcing off of the timer itself. They are basically heavy duty relays.

 

[shimz]

How? If one phase is off then there is no path for the circuit to be complete.

Cobby is right, it is considered single phase, but the legs are 180° out of phase. There is still the neutral line, so the circuit persisted, released some of the magic smoke in the lumitek ballast and scared the shit out of me. Luckily there was enough smoke left to keep it running for another 3 years, lol.

 

[Renfro]

there is single phase and 3 phase power, the latter being pretty uncommon in non-commercial installations

240VAC is always single phase in US, even in a 480/240 system

I know that, I worked as an electrician for many years. Now a 240v feed is two hots (phases), if one if off the other can't flow either, unless there is a ground fault.

 

[Renfro]

Cobby is right, it is considered single phase, but the legs are 180° out of phase. There is still the neutral line, so the circuit persisted, released some of the magic smoke in the lumitek ballast and scared the shit out of me. Luckily there was enough smoke left to keep it running for another 3 years, lol.

There is no neutral in a 240v lighting feed, no ballast out there uses that.

 

[shimz]

At least in my house, if I cut 1 leg of a 240v feed, I still have 120v on the other relative to ground. Ground/neutral are tied together at the box, so it was like I was powering the ballast with 120v, which was a no-no for the 240v only ballast.

 

[Renfro]

At least in my house, if I cut 1 leg of a 240v feed, I still have 120v on the other relative to ground. Ground/neutral are tied together at the box, so it was like I was powering the ballast with 120v, which was a no-no for the 240v only ballast.

Your ground isn't supposed to be used unless there is a fault (short to ground).

 

[Renfro]

Trust me, I know. Unless it's a 4 prong with a neutral because the load uses 120v for something... If there is a ground fault internally it wouldn't matter what the timer did.

 

[shimz]

I get what you're saying. Unit may have been defective for all I know. My water heater timers (ge) cut both legs.

 

[Renfro]

My water heater timers (ge) cut both legs.

Yes a 240V feed should be switched on both hots.

 

[dstroy]

Of course you can still measure 120vac on a leg relative to "neutral". That's normal, and expected. The 240v circuit is still open.

At least in my house, if I cut 1 leg of a 240v feed, I still have 120v on the other relative to ground. Ground/neutral are tied together at the box, so it was like I was powering the ballast with 120v, which was a no-no for the 240v only ballast.

 

[Renfro]

Thing is there is no neutral on a ballast at 240 volts. gosh

 

[dstroy]

Thing is there is no neutral on a ballast at 240 volts. gosh

Yeah, I don't know what measuring 120v on the still hot leg is proving. If both aren't hot the 240v circuit is open.

 

[shimz]

Rick and Morty attack! Duck!

 

[Bookush34]

I had one of these peices of junk on my auto water system. Fucker stuck on and flooded my room with 20gals of water.

Now that timer runs my mixer for the rez.

Still want to get a 3x3 20gal food tray to catch it if I have a fuck up again.

 

[mytwhyt]

I use a 2'x3' cement mixing tray from HD, 23 gal, $12.50..