mvs sarma said:
if the charger output is measured without connecting any load, perhaps it has to show 13.8V
At this point with nothing connected it reads 12v.
Bumping to 13.8v would give me the extra 1.8 volts to keep the charger from complaining of low voltage. I notice many power supplies designed for chargers supply 13.8 volts.
mvs sarma said:
if the design is protected such that the supply would NOT switch ON without connecting battery, it is fine and you may have to connect a fully charged battery --then it will have to show 13.8V, at least after few minutes.. if you connect a normal battery that is partially charged, after some time the charging will be complete, where upon it will have to show 13.8.
It's more simplistic than that. I simply have to have the chargers plugged in first. Not to pull a load to turn the PS on (I use a 10watt 10ohm sand bar on the 5+v to ground for that) When you plug in charger after the PS is on it spikes the PS and causes it to go into protect mode. at any rate I don't have to be charging a battery. I can simply plug the chargers up and then flip the PS on, in turn the chargers come on and wait for my input as to what battery type to charge, what rate etc. It's a computerized charger.
mvs sarma said:
Don't expect the charger to show 13.8 by connecting a discharged / partially charged battery.
So it is normal for a power supply to drop voltage while amps are being pulled?
If so what are the rules of this? Should it not lose volts till the amps are pulling close to the max or close to the "max continuous" amp draw?
The point of bumping up to 13.8 is to give more of a Voltage ceiling to pull from. So instead of reading 11.6 on a 6amp draw it would read at or more than 12v.
mvs sarma said:
yes there is a way to test for full load current. you may connect a battery and start the charger. then add artificial load like high wattage head lamps , or a artificial load resistor -please take precautions for dissipating the heat. (total wattage will be 12*20=240Watts.) then you may remove the battery once charger switches ON. (this method will help switching on for those chargers having protection to startt only with battery in circuit).
Could a buy some high wattage 12v lights and make an array to run many at once each with it's own switch to turn off or on so I can bump the amp pull per light? Also is their a easier way?
I would like to get it with in 10% of what my max continuous amp pull is.
Going from 6amp pull to 15 is to much to get it down to 10% of the max continuous pull it.
Also I have a couple of these power supplies and 2 of them have no blown fuse and the fans kick and the fan lights flash (these ps have fans with fancy led in them) and then it goes off. Instantly as if it has a dead short on the DC side. I have looked everything over and there is nothing visible. dry sockets, cracks, garbage shorting anything out etc. I assume it's a capacitor or something of that type. I do know one if not both have had more than the rated amps pulled form them and I guess the Protection did not kick in and shorted one of the components.
Thanks for the help