Newbie trying to set up Megawatt for charging

DieselBurps wrote:
I have the first voltage amp meter that is linked, purchased from amazon. Can anyone tell me where to hook up the yellow wire? I know red + and black - go to their respective spots on the megawatt but am unclear what to do with the Yellow wire?

If you are referring to


The yellow wire ties to the shunt negative.

If you are referring to


The yellow wire connects to battery positive

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

I have the first voltage amp meter that is linked, purchased from amazon. Can anyone tell me where to hook up the yellow wire? I know red + and black - go to their respective spots on the megawatt but am unclear what to do with the Yellow wire?

Reality is mean

No amount of righteous indignation or political finger pointing stands a chance against it.

I in my youthful wisdom and arrogance signed up for UDT tryouts at boot camp.

If I lasted 60 seconds it would be a miracle. One person lined up behind partner. Jump on piggyback. Wade into estuary. Knee deep muck. Fall. Get plastered with evil smelling muck. Put tail between legs. Retreat back to company barracks. Stand and scrub dungarees at concrete clothes washing slab while buck naked. Supposed to build character.

MEXICOWANDERER wrote:
Worst case scenario manipulation. Virtually worthless

I wonder what the Navy Seals would think of that phrase ... especially the virtually worthless part?

Don't they quote something like "Prepare For the Worst and Hope For the Best"?

It's been my observation that many RV'ers (none who participate in these forums :B ) "Prepare For The Best and Assume That's What Will Happen".

Or....

Worst case scenario manipulation. Virtually worthless

"What do I do to prevent an asteroid coming through the living room drapes?"

"Help! I've Fallen And Can't Get Up!"

Ring up room service and have them come and set the thermostat.

If it's one thing this forum excells at, it's hand wringing.

I've been using the meanwell rsp-500-15 for 4+ years now.

The ability to hold absorption voltage as long as is required to reach full charge, is responsibe for the exceptional service I am getting from my current AGM battery.

Fear of overcharging is a bit silly, its kind of like saying:

I hope the next time I drive, that i can remember I am supposed to stop at a stop sign and it would be better if my car braked automatically at red lights and stop signs so I can concentrate on updating my instagram account.

https://www.ebay.com/itm/Intermatic-FD6HH-6-Hour-Countdown-Decorator-Decora-Style-Timer-Switch-SPST-Ivory/162914076971?epid=1901006316&hash=item25ee6f892b:g:cWYAAOSwPb9ajvPl:rk:2:pf:0

This one even has a HOLD which should only be used when the power supply is set on long term voltage maintenance better known as FLOAT.

It is installed between the wall socket plug and the power supply.

This is a LIFETIME switch. When your children are in a rest home, this switch will still work fine. It is not a chew and spit purchase. It needs a PLASTIC duplex box and two ROMEX wire strain relief clamps from any hardware store.

And ALL of my seven Megawatts have an actual measured and remeasured ADJSUTABLE voltage range between 10.07 volts to 15.47 volts. Is there some Kryptonite battery out there that this will not agree with?

Meanwells are different. choose the dash fifteen model like the 1500 watt model that is the basis of the charger I am building. Because of the micro-soldering needed with the HIROSE connectors I DO NOT recommend this model for folks wishing knob adjustable remote voltage control.

From a Starbucks in Chula Vista. Spent the afternoon and night being poked and prodded. Temperament of a snapping turtle.

OP I sent you a PM from the nurse's station yesterday. Whoa talk about a nuclear RN when she found out.

Anyway forgetting about a Megawatt charging, boiling pot on the stove or a child in a hot car is unforgivable. Period. I'm in my mid-seventies. Do some of you need a keeper following you around all day? Yeah I'm crabby but what I write is life, like it or not. It's not about the time, it's not about an aged memory it's about laziness or sloppiness in failing to institute help in remembering that something important is happening and that failure is not an option.

Is is too difficult to set a watch? Set an alarm clock? Put the device on a timer?

The skull and crossbones grade warnings I see here are just silly. YES you can hurt batteries. Yes the melted pot can burn down your house. Our manufacturer gave us a mass of gray matter between the ears. Instead of issuing warnings, issue recommendations for EASY TO USE TIMERS.

Now that I have punctured some hides, I'll give thanks that I have a friend who will drive me to my PO box and retrieve the three INTERMATIC 6 hour wind-up spring timers amongst the baggage parcels waiting for me.

Jeezo! Hospitals kill the innocent. Torture. The room lights come on 6 times between ten PM and six AM.

theoldwizard1 wrote:

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.

That exactly hints at why the discontinuation of the "T" version of the Parallax RV converters was sad to see. Every time power was switched OFF and then back On ... it went to, and held, a 14.X boost voltage for 4 hours, then it would automatically switch back to a 13.X voltage float voltage and would hold that float voltage until someone interrupted power to it again.

It would have been perfect for some RV battery setups to this very day. For example, my AGM RV batteries require in the range of 14.4 volts for boost and 13.6-13.8 volts for float. With one of the Parallax T converters, all I would have to do for a fast boost charge anytime would be to quickly flip the panel switch to it OFF and then ON to begin a fast charge for 4 hours. No messing around with purchase of another power supply and a timer required.