Upgrade my control panel

n3qik
n3qik Solar Expert Posts: 741 ✭✭
Well, got some time this weekend to to finish the controller. The PLC is programmed to turn the outside lights on at night, turn my battery charger on when the batteries get below 11.5VDC. Transfer my gas heater and computers from the grid to the inverter when the batteries get fully charged. I have allowed for some future expansion. Now lets see what blows up!!

HPIM0452-web.jpg

Comments

  • SolarJohn
    SolarJohn Solar Expert Posts: 202 ✭✭
    Re: Upgrade my control panel

    I've spent most of my weekend working on something similar. I've built a circuit that allows me to set a low threshold voltage and a high threshold. When the batteries drop to the low threshold setting, a relay turns the inverter off. The Transfer Switch then connects the loads to grid-power instead. The inverter will not be turned on again until the battery voltage reaches the high voltage threshold setting. I'm testing the circuit right now with 12.25 volts for the low threshold setting, and 14.5 volts for the high voltage threshold setting. I've connected a data logger, and I'll probably let it run until next weekend. If tests are good I'll wire this into my system permanently. If I have any glitches, I may redesign with a microprocessor circuit. I've been providing details on my blog:

    http://solarjohn.blogspot.com

    I would appreciate comments from others who've done similar things.

    John
  • n3qik
    n3qik Solar Expert Posts: 741 ✭✭
    Re: Upgrade my control panel

    John
    Just a word of warning, refrigerators and freezers do not like power interruptions when they are on. If they are running and for the second the transfer switch switches over the the compressor will shut down and will have a very hard time restarting due to the high side freon still at high pressure. You should have a delay of 5-10 minuets between when power is turned off and then turned back on. Also may want to add a second delay so both do not turn on at the same time.
  • SolarJohn
    SolarJohn Solar Expert Posts: 202 ✭✭
    Re: Upgrade my control panel

    Thanks for the info Ken,

    For better control, it looks like I'll have to consider the microprocessor option. I've been avoiding that because of the time it will take to design, build, program, test, reprogram, test again, etc. Are PLC's expensive?

    John
  • n3qik
    n3qik Solar Expert Posts: 741 ✭✭
    Re: Upgrade my control panel

    Retail pricing is $125 for the PLC, $80 for the cable and not sure about cost of software.
  • SolarJohn
    SolarJohn Solar Expert Posts: 202 ✭✭
    Re: Upgrade my control panel

    I thought PLC's cost $thousands. Can you provide a little info about yours so I can research that? Thanks!

    John
  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: Upgrade my control panel

    John,

    Another "PLC" to consider is Morningstar's Relay Driver (~$145). It appears that it would interface very nicely with your Tristar controller. You can download the programming software for free to "try before you buy".

    See: http://www.morningstarcorp.com/products/RelayDriver/index.shtml

    HTH,
    Jim / crewzer
  • n3qik
    n3qik Solar Expert Posts: 741 ✭✭
    Re: Upgrade my control panel

    I just downloaded the software for the Morningstar Relay Driver. Very nice :D.
    At a list of $ 169, It is a good buy.
  • SolarJohn
    SolarJohn Solar Expert Posts: 202 ✭✭
    Re: Upgrade my control panel

    I've looked at the manual and software for the Morningstar relay driver and it looks like that will do the job nicely. I like to tinker, but I think I'll go with the Morningstar product instead of reinventing the wheel with my circuit. Thanks Jim and n3qik for pointing me in the right direction.

    John
  • SolarJohn
    SolarJohn Solar Expert Posts: 202 ✭✭
    Re: Upgrade my control panel

    I wish that the Morningstar Relay Driver included a real-time-clock. In addition to load control based on battery voltage, I'd like to have the ability to turn on a battery charger at a time of day when electric rates are lowest. I guess I'll just have to do that with a simple timer.

    John
  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    Re: Upgrade my control panel
    SolarJohn wrote: »
    I wish that the Morningstar Relay Driver included a real-time-clock. In addition to load control based on battery voltage, I'd like to have the ability to turn on a battery charger at a time of day when electric rates are lowest. I guess I'll just have to do that with a simple timer.
    John

    Insure your timer clock is driven from a un-interruptible power source. You don't want a couple of 10 minute glitches to slow your timer down, so that it shifts you to a high rate period.
    My suggestion would be to have it kick in the final hours before dawn, if that's a cheap rate, and then you start the day with topped off batteries, and could even equalize off solar.

    And if it was a cloudy day, you might want to have the charger kick in ASAP when the rates go low (11pm ?) to get charge into the cells, so they don't sulphate.

    And don't get burned by Std / DST shifts !

    There's a couple of scenarios for you !
    Powerfab top of pole PV mount | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
    || Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
    || VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A

    solar: http://tinyurl.com/LMR-Solar
    gen: http://tinyurl.com/LMR-Lister ,

  • n3qik
    n3qik Solar Expert Posts: 741 ✭✭
    Re: Upgrade my control panel
    SolarJohn wrote: »
    I wish that the Morningstar Relay Driver included a real-time-clock. In addition to load control based on battery voltage, I'd like to have the ability to turn on a battery charger at a time of day when electric rates are lowest. I guess I'll just have to do that with a simple timer.

    John

    John,
    You can set any/all relays base on battery voltage. If you did download the software, open it up and go Advanced button-Threshold- Tristar- Control Address 1, Control Variable- Battery Voltage.
    Timers- I got 2 of these from Harbor Freight
    http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=95205
  • SolarJohn
    SolarJohn Solar Expert Posts: 202 ✭✭
    Re: Upgrade my control panel

    Thanks for the link Ken, I've bookmarked it.

    Does that timer lose it's memory if the power is interrupted for a second? If it does, I might be better off with a mechanical timer instead.

    John
  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: Upgrade my control panel

    John,

    Here's a digital timer to consider: http://www.intermatic.com/Default.asp?action=prod&pid=203&did=5&cid=43&sid=114

    I've used its predecessor with great sucess for ~19 years. I think it's ~$20 at the "big orange box"

    HTH,
    Jim / crewzer
  • SolarJohn
    SolarJohn Solar Expert Posts: 202 ✭✭
    Re: Upgrade my control panel

    Thanks Jim,

    It has "battery backup", a feature that I need.

    John
  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: Upgrade my control panel

    John,

    My local HD was out of stock today on the DT17C. The DT27 ($18 ) appears to be a more-than-satisfactory alternative.

    HTH,
    Jim / crewzer
  • n3qik
    n3qik Solar Expert Posts: 741 ✭✭
    Re: Upgrade my control panel

    Well no smoke so far. I did get 110AH on Sunday:D and only 24.8AH today:cry:

    Fine tuned the on/off voltages for the AC loads and charger. Now can't wait till summer and get some better amphours.
  • crewzer
    crewzer Registered Users, Solar Expert Posts: 1,832 ✭✭✭✭
    Re: Upgrade my control panel

    NOTICE: Intermatic model DT27 timers with the "04B" date stamp have been recalled.

    See: http://www.cpsc.gov/cpscpub/prerel/prhtml08/08157.html

    :grr
    Jim / crewzer