Newbie trying to set up Megawatt for charging

I have the S-350-12. They have 3 terminals per side. I used 6, 3' 10AWG stranded. I crimped 12/10awg fork terminals on each wire for the power supply end and bundled the 3 and crimped a 8awg eyelet on the battery end. Make sure the terminals for the power supply end will fit the power supply terminal strip.

To measure current I bought This. If you don't have a voltmeter you may be better off with This

I adjust my power supply output to 14.5V before I connect it to the battery to allow for line loss. When it gets down to 1A my battery voltage will be ~14.4V.

A timer is a good idea, set it and forget it

DieselBurps wrote:
I would probably spring the cash for the Meanwell but I am looking to use the megawatt for 6 months to 1 year max. I will be in Mexico for the next 3 months and I found down there my solar has a hard time keeping some days, so figured I should add a battery charger to the mix to run for a few hours in the morning.

Megawatt and Meanwell are NOT battery chargers ! They are AC to DC fixed voltage, power supplies. They have very limited amount of manual range of adjustment.

Will they charge your battery ? ABSOLUTELY, if you are charging it at the battery manufactures recommended voltage. THEY WILL COOK YOU BATTERY JUST AS EASILY ! Run them on a old fashioned mechanical 60 minute timer.

The adjustable range on the Meanwell, at least from the factory, is not that wide. My 12v 20a Meanwell goes to 13.7 which is OK, but not the ideal 14.4+

The 15v version would probably be a better choice.

Just in case anyone thinking of buying a Meanwell.

DieselBurps wrote:

Adding maybe something like this to the Megawatt to measure voltage and amps

https://www.amazon.com/DROK-100105-100-300V-Multimeter-Amperage/dp/B07GB9TW6H/ref=sr_1_6?ie=UTF8&qid=1543537547&sr=8-6&keywords=digital+volt+amp+meter

That device measures AC volts and amps.

You want a DC Volt Ammeter

I would probably spring the cash for the Meanwell but I am looking to use the megawatt for 6 months to 1 year max. I will be in Mexico for the next 3 months and I found down there my solar has a hard time keeping some days, so figured I should add a battery charger to the mix to run for a few hours in the morning.

So it sounds like I am looking at having a shop make me up some cable with clamps out of #7 or#8 wire.

Adding maybe something like this to the Megawatt to measure voltage and amps

https://www.amazon.com/DROK-100105-100-300V-Multimeter-Amperage/dp/B07GB9TW6H/ref=sr_1_6?ie=UTF8&qid=1543537547&sr=8-6&keywords=digital+volt+amp+meter

#4 wire for a 30 amp charger close to the battery? I would be at #8 max.

Add an external computer fan to the top of the mega watt, blowing air into the mega watt

Just attach it to the terminals
Use a digital meter set the voltage to the desired level, without being connected to the batteries

Voltage will rise to the set point as the batteries charge

Monitoring the amps is a good idea
400 watts at 30 amps is only 13.33 volts
14.4v*30 amps is 432 watts..oops the reason for the extra fan

GordonThree wrote:

That's a kill-a-watt for measuring power. The megawatt is a brand of power supply... http://megawattpowersupplies.com/

Yes, of course, I should have known that. Thanks.

One device called a Megawatt is a power supply. I have the 30 amp model which when pushed hard gets hot and smells like it could go into melt down. I also have a Meanwell power supply which can be flat pedaled and does fine. Meawell was about twice the price. Wish I had bought it first.

You will be driving so watch for voltage rise.