30 amp 12v timer switch?

[createthis]

I'd like to have my midnite classic 150 charge controller on a timer. I'd like it to be on during daylight hours and off at night. Perhaps even using a photosensor. Does such a thing exist? If not, what's the best way to build one? I'm not sure a relay would be ideal. I'd prefer to expend power switching the state, but not maintaining it. Servo switch?

[Bala]

Why?

[Sunking]

You cannot disconnect the batteries without disconnecting the panel first.

You cannot connect the panels until the batteries are connected first.

Try again.

[Mike90250]

When you disconnect the battery, the memory runs off the coin cell (that you remove the shipping tab from when you install) I think I recall it has a 2 month life, so you get 4 months or less with your auto-disconnect, and then the Brain goes dead and you have to re-program it. Every 4 months after you change the battery

[createthis]

Why?

Draws 5 watts when it's on. Too much power.

[createthis]

When you disconnect the battery, the memory runs off the coin cell (that you remove the shipping tab from when you install) I think I recall it has a 2 month life, so you get 4 months or less with your auto-disconnect, and then the Brain goes dead and you have to re-program it. Every 4 months after you change the battery

I could always wire a dummy coin cell from another power source. This is less than ideal, but it's not a deal breaker.

[createthis]

You cannot disconnect the batteries without disconnecting the panel first.

You cannot connect the panels until the batteries are connected first.

Try again.

When it's dark, cutting the power to the battery works just fine. I just want to shut it off at night.

[Mike90250]

If the 5 w is too much power, look at the Morningstar MPPT 60. It's about the same ratings, but no display. It has a web server internally. And no screaming fans.
And I think it has less idle power. The Classic already has an internal relay to cut off some of the circuitry,

Dude - it's a monster 80A charge controller. With the large battery banks you connect it to, a 5w 18hr draw (90watt hours) is almost nothing. If the 5w is killing your batteries, something else major is wrong,

The reliable way to do it, is to use a solid state relay, controlled by a dusk-dawn lighting controller. And hope the PV array on the classic, fires up AFTER the SSR has powered up the controller. If the Array ever powers the controller before battery power is active, you are going to hurt.

[createthis]

The reliable way to do it, is to use a solid state relay, controlled by a dusk-dawn lighting controller. And hope the PV array on the classic, fires up AFTER the SSR has powered up the controller. If the Array ever powers the controller before battery power is active, you are going to hurt.

Doesn't an SSR use power while it's on? I suppose I could use two switches at the same time (one on the input, one on the battery) to eliminate the risk of that happening. However, what is the risk there? Would the classic be damaged if the battery was disconnected but the array was active? I don't see any warnings about that in the user manual. Wouldn't the same thing happen if a fuse or breaker on the battery tripped? Seems odd that would damage the classic as the purpose of such devices is to protect the equipment.

[Mike90250]

Well, switching the battery of the controller is not normal operating procedure. What's the big concern with a couple watts ?

[createthis]

Looks like the thing I'm looking for is probably called a "Latching Contactor". Momentary power to coil engages switch, permanent magnet holds it in place. Momentary reverse power to coil disengages. http://www.ametekswitch.com/products...tors-List.aspx

[Sunking]

FWIW you are really wasting your time and money trying to do this and asking for trouble. If your panel wattage so severely undersized as it cannot replace less than 100 wh a day to your battery, or is so small it cannot handle 100 wh with a 80 amp controller you have huge problems. I really do not think many are going to offer you help for this as you have already noticed. Just not worth the effort.

[inetdog]

Brutally frank, but good advice.

[Sunking]

Brutally frank, but good advice.

You know me I don't mince words, get right to the point, and is not personal. Trying to save this guy a lot of trouble, time, and some coins.

[createthis]

FWIW you are really wasting your time and money trying to do this and asking for trouble. If your panel wattage so severely undersized as it cannot replace less than 100 wh a day to your battery, or is so small it cannot handle 100 wh with a 80 amp controller you have huge problems. I really do not think many are going to offer you help for this as you have already noticed. Just not worth the effort.

I understand it's non-standard. I don't understand how it's "asking for trouble", however. Is it inherently dangerous in some way?