amp readings

sam c
sam c Registered Users Posts: 16
thanks to bb.& icarus, my pv is up and running, have a question, I ck the amp readings on the + side of the pv got a reading then ck the - side and it was higher, is this because the true path of the electrons is - to + or do I have a Resistance problem in the batt
thanks sam

Comments

  • niel
    niel Solar Expert Posts: 10,300 ✭✭✭✭
    Re: amp readings

    unless you are using the meter wrongly or you are bypassing the bad section with the meter, both current readings should be identical.
  • sam c
    sam c Registered Users Posts: 16
    Re: amp readings

    dont think Iam using the meter wrong ( been using these kind of meters for over forty yrs) its a clamp on amp probe and fairly new. their is no doubt the - reading is higher by a lot as much as 1.5 amps
    I broke down a hydro gen system, the creek is going dry, and brought in pv
    the open v from the pv looks good but I have not ck the shorted didnt think I need to sam
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: amp readings

    Depending on the size of your DC current probe... Some of the larger ones (hundreds of amps) are not that accurate at lower loads...

    Also, sometimes there are parallel circuit paths--typically in the ground return where the current can take both the "-" return, but also the safety ground return if both the "-" solar panel and the "-" battery post are connected to your safety ground (so, I would expect the ground current to be less than the positive current if it is sharing two return paths).

    You can also try taking the current probe and put it around both the + and - leads... The total current should be zero amps (+/-). If not, you can also try other paths (like the safety ground path) and see if you have any current through it.

    Also, you can try and flip the probe over---Say it reads +10.0 amp on the meter, flipping it over should then read -10.0 amps--if it reads different--then you can see how accurate (or in accurate) it is.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • sam c
    sam c Registered Users Posts: 16
    Re: amp readings

    the problem appears to have been a case of heat stroke for the meter. i left it laying in the sun near the panels, checking during the day the out put of the panels, replaced the meter batt and moved it to the shade, all is well
    the info from the post was helpful thanks, sam