Best meter location?

paul12345
paul12345 Registered Users Posts: 15 ✭✭
I have a meter I want to permanently install. Readings are current 0-200A, volts, power, watt hour, and ampere hour. Should this be installed panels or battery side of controller? Is it worth installing anyway? How could I use this information? Sorry, lots of questions.

7 x 150w panels through PWM TriStar TS-45, into 220 AH Crown battery bank.

Comments

  • mcgivor
    mcgivor Solar Expert Posts: 3,854 ✭✭✭✭✭✭
    Battery side eliminates controller loses along with being able to read discharge values.
    1500W, 6× Schutten 250W Poly panels , Schneider MPPT 60 150 CC, Schneider SW 2524 inverter, 400Ah LFP 24V nominal battery with Battery Bodyguard BMS 
    Second system 1890W  3 × 300W No name brand poly, 3×330 Sunsolar Poly panels, Morningstar TS 60 PWM controller, no name 2000W inverter 400Ah LFP 24V nominal battery with Daly BMS, used for water pumping and day time air conditioning.  
    5Kw Yanmar clone single cylinder air cooled diesel generator for rare emergency charging and welding.
  • paul12345
    paul12345 Registered Users Posts: 15 ✭✭
    Thanks, the meter is marked on one end 'source', on the other 'load'. So I guess if I want to read discharge the 'source'  should be connected to the battery?
    7 x 150w panels through PWM TriStar TS-45, into 220 AH Crown battery bank.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,433 admin
    You need to look at the meter specifications closely...

    Yours sounds like a standard power meter--For example, connect between battery bank and the loads. Many of these types of meters only "count up"--And you may be able to reset back to zero (once a day, once a month, etc.).

    And there are other meters that are "bi-directional". Current flows one direction and they "count up", current flows the other direction, and they "count down".

    And there are meters that are specifically designed as a Battery Monitor... They not only count up (such as recharging a battery bank) and count down (discharging a battery bank), they also usually have some sort of process to "reset" to 100% State of Charge (like hold 14.8 volts for 2 hours). And the also have fudge factor(s) that allow for battery losses.

    Battery Monitors can, and do, drift... If you do not have the "reset" to full, and reach that point once a week or so--They can drift and become inaccurate for state of charge.

    https://www.solar-electric.com/search/?q=battery+monitor (examples of "nice" battery monitors)
    https://www.amazon.com/s?k=batttery+monitor (some less expensive battery monitors)
    https://www.amazon.com/s?k=dc+ah+WH+meter (mixture of DC meters and battery monitors)

    Be very careful reading the specifications for Energy Monitors--It is not always clear if they only count up/count up&down/reset to 100% when battery is full...

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • paul12345
    paul12345 Registered Users Posts: 15 ✭✭
    edited April 2021 #5
    This stops measuring after 6554W. Then has to be reset to zero. I would like to set this up to read both battery discharge into the inverter & the DC coming directly from the battery.  Perhaps using a bus and then connecting the negatives into common ground.

    Edit: not 6554W, should be 6554 Ah
    7 x 150w panels through PWM TriStar TS-45, into 220 AH Crown battery bank.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,433 admin
    AC inverters can draw a lot of current (a 1,200 Watt AC inverter can draw >100 Amps @ 12 VDC battery bus)... So make sure that your meter (and shunt, if used) is rated for that.

    I am not sure where you want to mount the meter/what you want to measure. There are folks that have installed two or more of these meters (measuring AH/WH from charger, AW/WH to loads, etc.).

    Also... Battery bus and ground wiring needs to be correctly addressed. You are talking about some relatively high current and different setups (cabin/home, RV, etc.)... And, depending on the make/model of DC monitor you have--Many use a precision shunt (power resistor) which is generally mounted in the ground/return lead (usually the shunt is mounted in the ground wiring so that there is no chances of a dangerous short circuit--Because the ground wiring is already at zero volts).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • paul12345
    paul12345 Registered Users Posts: 15 ✭✭
    Thanks BB can't do that then. Back to plan B. Thanks.
    7 x 150w panels through PWM TriStar TS-45, into 220 AH Crown battery bank.