Optima top or side?

I have been finding most of the info I need to put together my small setup thanks to all the excellent information available here. :)

My questions are:

1. I have Optima batteries (3 in Parallel) and the question is should I use the side or the top terminals?
(I haven't seen anyone use the sides, but I thought I'd ask)

2. If I use the top should I use marine adapters and cables with rings (picture 1)
or cables w/ clamps?

3. I live in an apartment so the solar panels will only be hung out in emergency situations and temporary cables run to the rest of the equipment in the basement.
To maintain the battery charge, I will be topping them off one at a time, once a month. The AC charger I have (CTEK Multi US 3300) won't permit all 3 to be charged at the save time so I am thinking of adding a knife switch (picture 2 & 3) to each battery so that I can take any one off line and clip on the charger.
Yes, no, maybe?

Thank you in advance.

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Optima top or side?
    1. I have Optima batteries (3 in Parallel) and the question is should I use the side or the top terminals?
    (I haven't seen anyone use the sides, but I thought I'd ask)

    According to this Ehow link:
    Side battery terminals are a fad that came and went--almost. Some car manufacturers are still installing them, but most have gone back to the post terminals on the top of the battery. Side terminals are hard to manipulate and the bolts that hold them on are tiny with threads that are easily stripped.

    So I would stick with post (or bolt up) mounting (depending on the deep cycle batteries you end up using).
    2. If I use the top should I use marine adapters and cables with rings (picture 1) or cables w/ clamps?
    I do not like the Ring lugs with "saddle type" camps (that clamp the stripped wire). I do not think they are very rugged or reliable.

    Use cables with swagged ends on them (order to length or get your own hammer crimping tool and parts+wire to make up your own).
    3. I live in an apartment so the solar panels will only be hung out in emergency situations and temporary cables run to the rest of the equipment in the basement.

    This raises a lot of questions...
    • Solar panels fixed when outside so they don't get blown over and damaged?
    • Reasonable southern exposure to sun--No shadows/wires/etc. from ~9am to 3pm?
    • You have a safe place to store panels (they are tempered single weight glass, typically--if scratched/knocked hard enough, the entire panel will shatter and be useless).
    • Will you connector the panels with polarized plugs (panels connected backwards to a battery bank can be destroyed almost instantly.
    • Solar Charge Controller picked out?
    • How long will the cables be from the solar panels to the battery bank?
    • Wiring properly done so you don't get opens/shorts?
    • Fuses/Breakers installed as appropriate?
    • Normal flooded cell batteries do out gas and can have acid mist spread around to nearby objects.
    • Batteries need to be ventilated and protected from children/metal objects/etc. accessing the tops of the batteries/terminals (acid, high energy wiring, etc.).
    • AGM/Sealed batteries are better--but still can vent if overcharged/aging out (Yellow tops may be AGM--cannot tell from specs. I found).
    • What power are you sending to the basement (12 volts, 120 VAC) and how much (run and surge amperage)?
    • What gauge cable will you use to send the power down and how long will it be? Fused (if 12 vdc)?
    • Have you sized your battery bank and solar array to the loads you need to support?
    • Backup genset + fuel if no-sun for a week or so (stormy weather backup)?
    To maintain the battery charge, I will be topping them off one at a time, once a month. The AC charger I have (CTEK Multi US 3300) won't permit all 3 to be charged at the save time so I am thinking of adding a knife switch (picture 2 & 3) to each battery so that I can take any one off line and clip on the charger.
    Yes, no, maybe?

    Over time, you will probably tire of the once a month, over a several day period, having to recharge your battery bank... You probably would be better off getting battery charger that supports that size battery bank.

    I am not a big fan of having to manipulate battery charger clips to recharge a fixed / permanent installation. Things get dropped on the battery bank, wires get cut/old/hard and insulation cracks, etc... It would be better to have the right charger permanently wired up.

    Personally, I use a "cheap charger" and a lamp timer. I set the timer to 1 hour per day (+/-) to turn on and charge the batteries. That adds up to ~30 hours per month--very similar to charging the batteries 1 day per month (if you don't get a charger with float setting). Or in my case, even small chargers designed to float the batteries still seem to boil the batteries dry for me.

    Also, if you have the need to quickly recharge the battery bank (a few hours of power a day, or a backup AC genset)--the small trickle charger will not cut it. You need a good quality deep cycle battery charger that can output 10-20 amps or so. This will allow you to quickly recharge the batteries during the day and use them at night (for example).

    Tie a 20 amp 12 volt charger with an eu1000i genset--and you have a fairly fuel efficient backup power system (siphon fuel from the car for a few days, or more, of generator power).

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • n3qik
    n3qik Solar Expert Posts: 741 ✭✭
    Re: Optima top or side?

    The Optima's are AGM batteries.

    I am using the side terminal. I felt the top mounting was to hard to insulate any expose conductors/hardware. With the bank pushed together, only the end battery has exposed conductors/hardware.

    As to bolt/stripping issue. Used a longer bolt. Screwed it in finger tight, then used a nut to tighten the wire/lug to the battery post. Most OEM sidemount bolt have only 2-3 threads. So yep, they suck.
  • System2
    System2 Posts: 6,290 admin
    Re: Optima top or side?

    Bill, thank you for replying,

    The "cheap charger" and a lamp timer sound like a good idea. I searched around and the only cheap ones don't say anything about charging batteries in parallel. Any suggestions on this would be appreciated.
    The only one (reasonably priced) I found so far is Schumacher SC-8020A. http://www.batterychargers.com/Documents/00-99-000826.pdf
    (It also doesn't say anything about charging batteries in parallel, but this one says the charger will be set for small battery size (2A) and 12V AGM on power up.
    (good for timer use)

    Even though my setup will never see an inspector, (or any of the energy rebates :cry:) I'm trying to keep it in code as much as possible so I appreciate the questions.


    This raises a lot of questions...

    * Solar panels fixed when outside so they don't get blown over and damaged?
    - I'm working on a frame that will hold 2 panels per frame (approx 2' wide) and could be easily hung out any window and anchored by the window frame.
    Low wind area.
    Still a lot of testing to perform on this. I'll post pictures when this is finished.

    * Reasonable southern exposure to sun--No shadows/wires/etc. from ~9am to 3pm?
    - Winter we get 3hrs + -?

    * You have a safe place to store panels (they are tempered single weight glass, typically--if scratched/knocked hard enough, the entire panel will shatter and be useless).
    - Spare room.

    * Will you connector the panels with polarized plugs (panels connected backwards to a battery bank can be destroyed almost instantly.
    - Currently using polarized but I plan to upgrade to use MC4 connectors when I change panels.

    * Solar Charge Controller picked out?
    - I have the Morningstar ProStar 30 display w/battery sensor.

    * How long will the cables be from the solar panels to the battery bank?
    - Approx 25-30'.

    * Wiring properly done so you don't get opens/shorts?
    - Oversized whenever possible and all UL approved. (no welding or auto).

    * Fuses/Breakers installed as appropriate?
    - Using Midnite Solar Mini-DC panel (w/GFP) at battery bank and combiner DC breaker panel before going to the solar panels.

    * Normal flooded cell batteries do out gas and can have acid mist spread around to nearby objects.
    * Batteries need to be ventilated and protected from children/metal objects/etc. accessing the tops of the batteries/terminals (acid, high energy wiring, etc.).
    * AGM/Sealed batteries are better--but still can vent if overcharged/aging out (Yellow tops may be AGM--cannot tell from specs. I found).
    - These are AGM and are open to the basenent for venting if needed.

    * What power are you sending to the basement (12 volts, 120 VAC) and how much (run and surge amperage)?
    - The panels are from HF ( I know, cheap) with a total of 60 watts at 12 volts. I plan to get more efficient ones.

    * What gauge cable will you use to send the power down and how long will it be? Fused (if 12 vdc)?
    - Each panel is fused in a junction box at the panels (pair), then a small breaker panel (indoors) and then 25-30' (10ga) to the basement.

    * Have you sized your battery bank and solar array to the loads you need to support?
    - For emergency I will use a couple of lights(led), radio, and charge my cell so I should be OK with the batteries.

    * Backup genset + fuel if no-sun for a week or so (stormy weather backup)?
    - I don't think that would go over very well with my neighbors. :)


    Ken, thank you for replying,

    I'm glad you replied as I saw on your hompage that you used Optima, but there were no pictures of the batteries and I was wondering how you connected them.

    Thanks for the great pictures. Nice clean layout.
    It doesn't look like you used lock washers. Are lock washers needed there?
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Optima top or side?
    The "cheap charger" and a lamp timer sound like a good idea. I searched around and the only cheap ones don't say anything about charging batteries in parallel. Any suggestions on this would be appreciated.
    For maintenance charging--1 Amp per 100 Amp*Hour charger is probably fine.

    You will have to monitor the resting voltage of the batteries as they get older--At some point you will probably need to increase the timer from 1 hour to 2-4 hours as the batteries age.
    The only one (reasonably priced) I found so far is Schumacher SC-8020A. http://www.batterychargers.com/Documents/00-99-000826.pdf
    (It also doesn't say anything about charging batteries in parallel, but this one says the charger will be set for small battery size (2A) and 12V AGM on power up.
    Nice charger--but I would wonder if you set it to run on a timer--Would it lose its settings when the power was turned off (or draw power from the battery bank when the AC power was off)?

    I was just using "dumb" chargers with the timer.

    Also, I would suggest getting a "real" battery charger that can charge you 150 AH of battery bank (~7-15amps would be fine). When the power returns, you can quickly recharge the batteries and be ready for the next outage.

    You can get an Iota 15 amp charger for $130 (good quality and can be operated by a Honda eu1000i genset).

    Or a Battery Minder for 2-8 amp charger designed for float charging for $125.
    * Reasonable southern exposure to sun--No shadows/wires/etc. from ~9am to 3pm?
    - Winter we get 3hrs + -?
    You get 3 hours equivalent of full noon-time sun... But you need the panel to be free of shadows most of the day to gather the sun.
    * Will you connector the panels with polarized plugs (panels connected backwards to a battery bank can be destroyed almost instantly.
    - Currently using polarized but I plan to upgrade to use MC4 connectors when I change panels.
    I don't believe the MC4 connectors are rugged enough for more than a few operations... I would pick something else (like the Anderson PowerPole Connectors).
    * Solar Charge Controller picked out?
    - I have the Morningstar ProStar 30 display w/battery sensor.
    A PWM controller may be an issue here... More below.
    * How long will the cables be from the solar panels to the battery bank?
    - Approx 25-30'.
    How many and what rating will be your solar panels?

    Sending "12 volts" (really ~17.5 volts) for 30 feet can to the charge controller can be a big problem with voltage drop.

    One way around the problem is to put two or three solar panels in series, then send the power 30' to a MPPT type charge controller. That will cut the current by 1/2 or 2/3rd's, and let you use much smaller gauge wire.
    * What power are you sending to the basement (12 volts, 120 VAC) and how much (run and surge amperage)?
    - The panels are from HF ( I know, cheap) with a total of 60 watts at 12 volts. I plan to get more efficient ones.
    I would suggest not to even bother... They are 2x the area (less efficient thin film panels) and are not really known for even meeting their specifications.
    * What gauge cable will you use to send the power down and how long will it be? Fused (if 12 vdc)?
    - Each panel is fused in a junction box at the panels (pair), then a small breaker panel (indoors) and then 25-30' (10ga) to the basement.
    That is OK voltage drop wise for this small array... But, I would be suggesting (assuming 150 AH at 12 volt battery bank):
    • 150 AH * 14.5 volts * 1/0.77 derating * 0.05 rate of charge = 141 watts minimum solar array
    For the same physical size solar panels as the HF units--you could get a single 135 watt (or so) solar panel.

    And, for emergency power, I would be suggesting 282 watts or more of solar panel (based on my guess of 150 AH battery bank).

    60 watts is really too small for that size battery bank (recommend 0.05 to 0.13 of rated battery bank capacity for solar array/battery charging).
    * Have you sized your battery bank and solar array to the loads you need to support?
    - For emergency I will use a couple of lights(led), radio, and charge my cell so I should be OK with the batteries.
    It is actually difficult to keep a "Large" battery bank charged with too little amount of solar panels.

    Many times, it is better to use a smaller battery bank with a small solar array instead. The batteries will charge faster and last longer (more cycle life).
    * Backup genset + fuel if no-sun for a week or so (stormy weather backup)?
    - I don't think that would go over very well with my neighbors. :)

    Yea, appartment life is a pain. The small Honda eu1000i is like a carryon suitcase and you can siphon fuel from your car. Noise wise, on a city street, you cannot even hear them running. Obviously, it is not safe to run a genset on the balcony (fumes, fire hazard)--but if you had to bring the batteries to the parking lot to recharge (or run an extension cord to the basement)--It is not a bad way to go.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • System2
    System2 Posts: 6,290 admin
    Re: Optima top or side?
    BB. wrote: »
    Also, I would suggest getting a "real" battery charger that can charge you 150 AH of battery bank (~7-15amps would be fine). When the power returns, you can quickly recharge the batteries and be ready for the next outage.

    You can get an Iota 15 amp charger for $130 (good quality and can be operated by a Honda eu1000i genset).

    The small Honda eu1000i is like a carryon suitcase and you can siphon fuel from your car. Noise wise, on a city street, you cannot even hear them running. Obviously, it is not safe to run a genset on the balcony (fumes, fire hazard)--but if you had to bring the batteries to the parking lot to recharge (or run an extension cord to the basement)--It is not a bad way to go.

    This looks like the charger I'll be getting. The Honda looks pretty good too, but will have to wait till after my tax refund comes in.

    A couple questions about using the Iota charger:

    -Should I leave it physically connected all the time? (through a fuse/breaker?)


    With the timer:
    -If not using the iq4 option, manually switch it to long-term float and 1 hr per night? (Then manually change to fast charging after use)
    -or-
    -If using the iq4 option, leave on all night? (I think this is the better choice)

    Thank you,
    Bruce.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Optima top or side?

    The Iota has a jumper... Jumper in is "high voltage" charging. Great for when the power has been out and you want to quickly recharge the battery bank. Also a good setting for use with a genset--Basically, generators are more efficient with ~50% or greater load--so having the charger dump current quickly and keeping the generator loaded can be a real fuel saver.

    Once the battery is charged, the jumper is pulled out and the batteries are kept at float.

    If you are going to leave the charger plugged in 24x7--leaving it at float is fine.

    Batteries are supposed to last longer if occasionally discharged once in a while (cycled) rather than setting at float 100% of the time.

    The IQ4 charger does do equalization every couple weeks (as I recall)--and that is really not a good idea for AGM batteries.

    When (if) you cycle the battery, just put the jumper back in until the batteries are fully recharged.

    AGM's can go for several months or more (depending on age/temperature) without any charging at all (they typically have very low self discharge)... So you don't really need to have them sit on float--But a short charge every day (lamp timer) or charge once every few months will work too.

    I am sort of a set it up for "automatic" charging rather than having to manual recharge every X weeks kind of guy.

    You should be able to leave the Iota chargers connected to the battery with or without AC power applied--But I would double check with Iota directly (or the Iota dealer).

    Fusing should be 15 amps * 1.25 NEC derating = 18.75 amps or 20 amp breaker/fuse. Fuse/breaker should be near the battery bank... Fuses are to protect the cabling from short circuits (don't want wire to catch fire/melt). Just gone fuse in the + lead should be fine.

    Usually you use heavier gauge wire than 12 awg @ 20 amps to avoid voltage drop. Also depends on how long the cable run is from the battery to the charger.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • System2
    System2 Posts: 6,290 admin
    Re: Optima top or side?

    Hello Again,

    I contacted iota and here is the info:

    Our DLS-15 will draw approximately 20ma from your battery if connected. It’s not enough to worry about unless you are storing the battery for a month or two.

    With the IQ4 the equalization stage only occurs if the DLS-15 is kept on for 7 days in a row. What we call the equalization stage is nothing more than our 3 stage charge cycle again. The maximum voltage your batteries will ever see is 14.8v for 15 minutes.


    From the IQ4 manual:

    The LED indicator will remain lit or flashing when the charger is unplugged or disconnected from the AC supply (de-energized). During this time, the IQ4 continues to monitor the battery voltage. If the battery voltage drops below a pre-determined voltage (Refer to Figure D for predetermined values), the IQ4 will automatically initiate the 3-Stage Charge (BULK, ABSORPTION, and FLOAT) once the AC input is re-connected.

    So it looks like if I use a timer and have it set for a few hours at night, twice a week it will take care of its own loss and also never go into "equalization".

    Let me know what you think.
    Thank you,
    Bruce.
  • vcallaway
    vcallaway Solar Expert Posts: 157 ✭✭✭✭✭
    Re: Optima top or side?

    I have the Schumacher SC-8020A. It is a great general purpose charger. The problem is that since it is designed as a portable charger it has to be reset each time it is used. It does not start charging until the battery type is set.

    If you watch the local parts stores have it on sale for around $60 to $70 fairly often.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: Optima top or side?

    Bruce,

    Sounds very reasonable to me.

    Timer most of the year for light charging. Run the iq4 during bad weather and from the generator to quickly recharge the bank when Utility power or generator power is available.

    The short equalize is not going to hurt anything the few times a year you may run it.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • dagr51
    dagr51 Solar Expert Posts: 72 ✭✭✭✭
    Re: Optima top or side?

    I have an Iota DLS 75 (660 ah, 12v battery bank). I leave my batteries hooked up to it and the charger on AC all winter (~ 4-5 months). No problems.