low voltage

System
System Posts: 2,511 admin
Hi
could someone help as to what equipment i would need to hook my generator up so it would automaticaly would come on when my voltage got to low in my batteries. i am currently using a trace dr series inverter with a battery charger in it
thanks would appreciate any help

Comments

  • RCinFLA
    RCinFLA Solar Expert Posts: 1,485 ✭✭✭✭
    Re: low voltage

    You will need a battery monitor that has some external relay control based on cumulative A-H used or at least low battery voltage alarm.

    The Victron BMV 600 Battery Monitor has a low batt alarm output.
    http://www.jamestowndistributors.com/userportal/show_product.do?pid=51843&familyName=Victron+BMV+600+Battery+Monitor

    The generator capability can make it a lot simplier.

    You have starter control and ignition switching to deal with at a minimum. Choking for a gasoline engine can be complicated. Once the generator is warm you can usually do without choking control.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,590 admin
    Re: low voltage

    Is your generator already configured to accept either a 2 wire or 4 wire generator auto-start signal from your Trace Controller (I am not sure which the Trace supports).

    As RCinFLA says--the "issues" with auto-start generally rest with how the generator is configured (what type of start/control signals; does the genset have its own controller to do the cranking, choking, cool down/shut down, emergency shutdown, etc.).

    For example, a little Honda eu3000i would make a very nice auto-start genset--but there are not any controllers/accessories (that I can find) that support a full auto-controlled eu3000i. The best you can find is a "remote start"--basically, turn on the ignition and you push a button for remote crank.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • RCinFLA
    RCinFLA Solar Expert Posts: 1,485 ✭✭✭✭
    Re: low voltage

    The DR series MSW inverters have no provision for external relay control. The SW series has.

    The DR series chargers are not great. They basically use the inverter isolation transformer in reverse with rectifier diodes. They are very critical to AC input voltage. The charger current is only during peaks of sinewave. This yields a poor power factor load on AC source.

    If you refer to your manual you will see a section that explains why it is very important to have 120 vac for DR charger. If generator output is a little low in voltage output it severely drops charger current output.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,590 admin
    Re: low voltage

    Lastly, look at the age of your DR system... Most of those older units are probably over 10 years old and may not even have factory support for parts and service (I will defend the company--it is very difficult to support electronics and other parts after a decade--pretty much everything used electronics wise is now obsolete and cost more than the parts in new designs)...

    At this point, you probably want to avoid putting too much DR related money into your system. At some point, it will fail and some sort of upgrade (with genset controller option, PFC charger, true sine wave output, etc.) that comes now with the current designs.

    Setting up a Battery Monitor (or voltage monitor) with an external PFC battery charger (power factor corrected) may be a reasonable option.

    Other things to think about--would you stay at the current battery bank voltage, or upgrade to the next higher level. What is the generator's output rating--As RCinFLA says, the old type battery chargers require very hefty gensets to provide useful energy for the battery bank (Basically, perhaps only 60% of the current from the genset actually is used to charge the battery bank because of the sine wave peak only charging current).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • System2
    System2 Posts: 6,290 admin
    Re: low voltage

    thank you for the valuable info.