Over current trip due to inrush current

[Aussierob]

Hoping someone may have an answer. I have a new Kid that will be installed in a remote cabin. I am testing it at home. To simulate the LED lighting load it will have, I have three MR16 lamps that draw 11.2Amps when on. I am finding that when the Kid reconnects after a low voltage disconnect, It immediately turns off the output and displays the "over-current" fault. The amp limit for the load is set to 30 amps. Does anyone know if the Kid is sensitive to inrush currents? If I disconnect one lamp, it will turn on the remaining two without problem, but it won't switch on three.

Thanks for any info.

Rob :-)

[Vic]

Hi Rob,

There are many different MR16,  now.   But assume that these MR16s that you are using are incandescent,  and that is why you asked about Inrush current.

Many incandescent lamps have very large inrush currents -- up to 10X the operating current,  perhaps more.

If I were a KID,  I would be sensitive to any overcurrent situation,  but do not use the Load terminals on the KID here,  so cannot respond to your question directly.

If you had a resistor that you could place on the Load terminals,  that would simulate the approximate load that the real LED lighting demands,  you could measure the voltage,  or perhaps place a small LED lamp,  with suitable current-limiting resistor to get an idea of how the Load function will behave when you have the real LED lights as a load ...   FWIW,  Vic

[Aussierob]

Thanks Vic. I know I could test it out, I am hoping someone (maybe a midnite solar someone) who has been through this can provide some insight. Maybe tested it on various loads and knows what it will and wont do.

Thanks.   

[mike90045]

If you are running enough LED lighting to need a 11.2A dummy load, you also better invest in sunglasses.

But seriously, 11A is enough to cause a noticeable voltage drop at 12V because you better spread that 11A of lighting out over a large area.

What happens if you switch on one lamp at a time, can you get all 3 lit eventually ?

[Aussierob]

Have my sunglasses      I am installing 13 LED lamps in a backcountry cabin so lots of spread. The system will happily turn on two of the MR16's but not three. In my real world application the lights will be on three circuits so I'm not worried about them all being turned on at the same time. I think in my application I'll be fine, but I could imagine someone with a 20-30 amp load having issues. It may be a filter or delay needs to be programmed in the firmware to allow an inrush. Of course the easy way out is to use a relay, but that adds complication, and one of the reasons to use a kid is that it has load switching built in.

Rob 

[Westbranch]

Are you running them off an inverter or 12 V?  Most MR (all?) are 12 v lights including the LED versions.. it it's a cabin go native....12 v that is...

[Aussierob]

No inverter in this system. Everything is 12v.

[Westbranch]

Ouch, that is ~ 50 W rating per LED, we had 3 @ 4 w, 12V native, MR16 LED lights in our old 512 Sq ft , 16' x 32' cabin and had oodles of light, it must be like an operating room in there...

[Aussierob]

No 50w LED's. I have some 35w and 50w MR16's as dummy load for testing. In the cabin we will have 13 5w LED lamps, all spread out.

[Bunkie314]

How about just turning on/off a 12V relay with the kid load terminal and connect the load to the battery? Fairly simple resolve with higher amp capacity if so desired. Don't forget to the fuse the relay feed.

[Aussierob]

Hi Bunkie,
I could do that, but it kind of defeats the purpose of having a controller with the switching built in. I'm pretty confident that my application will be fine, given there will be three circuits of load at about 2 amps each. It's not possible to switch them all on at the same time.

Rob