Slew Drives & Acuators

Hello does anybody know of a good supplier of slew drive and acuators for DIY array trackers? I need approximately 260 degree azimuth travel.


  • BB.
    BB. Super Moderators, Administrators Posts: 33,467 admin
    Re: Slew Drives & Acuators

    I have been saying that tracking systems are not worth the effort...

    But Dave Sparks has been saying that (especially for off grid systems that need lots of time to recharge a battery bank) that a little bit of maintenance with good hardware makes for a nice tracking system.
    Tracking offgrid is the number one way if your location supports it to get completely away from generator use. This goal is very hard to do on a reasonable budget but a tracker is the path. I can not tell you the absolute difference other than we went from 25 days our batteries did not complete charge down to 5 per year. The other feature is you are off battery power earlier in the day and can do more with a smaller battery system. Conversely you can run cooling in summer at 7pm long after the fixed array has gone to sleep.

    There just are too many variables but I would tell you a 2KW or slightly less tracker will do for most couples what 4KW fixed would do in winter up here in the Sierra. Winter is where the design is done and since all I do is trackers now it is my business model. I do not want phone calls!!! From my experience there just are too many days when an hour of sunlight at 9 am and another hour at 2 pm happen in winter. There are other scenarios of clouds and just plain weather that a tracked array is superior over fixed.

    If you like cold starting generators in the snow/ dealing with surges, doing alot more maintenance, having a big footprint of panels to deal with, a fixed array is definitely for you. I do like a fixed array with a tracker so I am reasonable! I probably would agree with most of the gridtie folks here except I tried it. Definitely no going back!

    I asked him what he found to be reliable:
    24V DC motors supplied as a package from Array Technologies i.e. The Wattsun !

    You can read about Wattsun here:

    And find out if they sell the actuators or will tell you their supplier.

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset