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Installing a timer for charging?

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What kind of timer? Make? Model? Cost if you know.

Good, ole' Intermatic T100 series are what most electricians know ($50-100), although there are "smarter" electronic versions.

http://www.intermatic.com/~/media/Intermatic/Documentation/Specifier%20Guide/003_T100%20Series_2pgs.ashx

The documentation isn't clear, it talks about rated for 40A loads, but isn't clear about continuous vs. intermittent. My guess is that officially, per the NEC, it's not rated for the 40A continuous load as its rating requirement would then be 50A.
 
24hr_timer.jpg


Typical wall mounted 24 hour easy to reprogram timer. Check to be sure the switch can be fully isolated from the mains so you can do this:

Clipper Creek CS-40 etc chargers offer two choices:

1. Grounding High/Off terminal will completely inhibit charging until it is released.
2. Grounding High/Low terminal sends signal to car to NOT charge, but only send enough current for housekeeping.

This has got DIY written all over it- should be easy job. Other EVSE probably have the same connections inside, check their infos. You can use telephone wire since it is low voltage.
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Typical wall mounted 24 hour easy to reprogram timer. Check to be sure the switch can be fully isolated from the mains so you can do this:

Clipper Creek CS-40 etc chargers offer two choices:

1. Grounding High/Off terminal will completely inhibit charging until it is released.
2. Grounding High/Low terminal sends signal to car to NOT charge, but only send enough current for housekeeping.

This has got DIY written all over it- should be easy job. Other EVSE probably have the same connections inside, check their infos. You can use telephone wire since it is low voltage.
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This seems to be a timer used on the pilot signal, rather than inline to disconnect the mains. So on the UMC, it means you would have to cut the cable to install it.

It's not too hard to build a timer, either. Take a 2-pole, 250V/50A contactor with 120V primary coil and connect a NEMA 5-15P to the primary coil. Plug that into a standard lamp timer (above). Plug the timer into a receptacle connected between L1 and N of a 14-50P plug to give it 120V, and connect one set of contactor secondary contacts to L1 & L2. Take a 14-50R receptacle and connect L1 and L2 to the other secondary contacts, connect N to the 14-50P's N, and tie all grounds together.
 
Good, ole' Intermatic T100 series are what most electricians know ($50-100), although there are "smarter" electronic versions.

http://www.intermatic.com/~/media/Intermatic/Documentation/Specifier%20Guide/003_T100%20Series_2pgs.ashx

The documentation isn't clear, it talks about rated for 40A loads, but isn't clear about continuous vs. intermittent. My guess is that officially, per the NEC, it's not rated for the 40A continuous load as its rating requirement would then be 50A.


Thanks for the link.
 
My timer is plain vanilla intermatic T104' 240v 40 amp. When I receive my MS I will plug in and check the max draw at the 50 amp breaker. I really hope the new firmware will have programmable start and stop times.

We've already seen the "4.3" branded firmware in Europe that shows delayed charging (I believe start-time only).

I'm doing a bit of research to see if the T100 series is rated for 40A intermittent or continuous loads.
 
I'm doing a bit of research to see if the T100 series is rated for 40A intermittent or continuous loads.

So after a few posts on a handful of sites to get a collective opinion, and receiving a call back from my AHJ today, it seems that the Intermatic timers are appropriate. The de-rating by NEC standards only pertains to conductors and overcurrent protection devices (breakers) but not other load controlling equipment.

So, a 40A Intermatic timer (T1xx series) is appropriate, if you can't wait for 4.3. :)
 
So after a few posts on a handful of sites to get a collective opinion, and receiving a call back from my AHJ today, it seems that the Intermatic timers are appropriate. The de-rating by NEC standards only pertains to conductors and overcurrent protection devices (breakers) but not other load controlling equipment.

So, a 40A Intermatic timer (T1xx series) is appropriate, if you can't wait for 4.3. :)

4.3 should be released pretty soon.. I'd wait.