Who can solve this puzzle for connecting a backup generator?!

tRE
tRE Registered Users Posts: 1
Hi everyone,
I just joined this forum after seeing how helpful so many people are here for solving problems that others are having.

I am hoping someone can please help me with my situation in trying to get my off-grid solar system hooked up to a backup generator for these cloudy periods in Ontario, Canada where my batteries aren't getting topped up enough by the sun. I need to ideally charge them fully when the sun goes down each day if they aren't full at that point and want to charge them as efficiently as possible.

Here's what I have:
-A Honda EU2200i generator (https://powerequipment.honda.com/generators/models/EU2200i) which outputs only 120V
-4 240 AH AGM batteries hooked up in series in a way that they make 24v
-Solar panels (doesn't really matter about them right)
-Outback FlexMax60 charge controller (assume this isn't important either?)

I do NOT have the ME-ARC control for the inverter, though I could get it if needed. I was told by a Magnum tech support guy I may need this to have the inverter shut off without overcharging the batteries if I can use the inverter in its charger function.

However, another electrical engineer fellow said I can't even use my generator with this inverter, since the generator is 120V output and the inverter needs 120/240 split phase. I don't understand this and am not positive it is true, but he seemed to know what he was talking about since he's an electrical engineer who owns a solar power energy shop.

I am considering getting a battery charger of some kind that just charges the batteries from the inverter when needed, but not sure if this is a good option. I guess I'd need some kind of smart charger that can do bulk, absorb and float, and prevents overcharge? As you can tell I know very little about all this.

Does anyone have any advice? Thank you so much in advance!
Regards,
Trent

Comments

  • mike95490
    mike95490 Solar Expert Posts: 9,583 ✭✭✭✭✭
    I don't know if your inverter model requires 240V to act as a battery charger, but if it does, you have 2 choices:
    a) get a 240V split phase generator
    b) get a 24V golf cart charger and use that with your generator.

    Sadly , most golf cart chargers only end up being about 60% efficient because they have poor power factor.  The inverter/charger will be very efficient because they have good power factor, but they need 240V sometimes

    What does your inverter manual say ?

    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 ,

  • Raj174
    Raj174 Solar Expert Posts: 795 ✭✭✭✭
    edited December 2020 #3
    Looks like it will accept 120V generator input, however the charge rate will have to be reduced to 50%. That's why you would need the ME-RC, ME-ARC or ME-RTR to change this setting.

    From the manual:

    2.3.5 Wiring the AC Input and Output

    The MS-PAE provides 120/240 VAC on the output, but the input may be wired either as a 120/240 VAC input or a 120 VAC input (to one input only) depending on the AC source. The AC output continues to produce 120/240 VAC with either the 120/240 VAC or 120 VAC input configuration.

    WARNING: DO NOT connect 120 VAC (same phase) to both AC HOT 1 IN and AC HOT 2 IN inputs. These inputs must be 180° out-of-phase (i.e., 120/240 VAC). If you only have a 120 VAC source, you may connect to either the AC HOT 1 IN or AC HOT 2 IN, but NOT to both or damage may occur.

    WARNING: Before making any AC connections, make sure the inverter is disconnected from the battery bank and that no AC power is connected to the inverter.

    Info: If providing only 120 volts to the inverter input, the charger must be turned down to 50% to prevent overheating from occurring.

    CAUTION: The inverter’s AC output must never be connected to an AC power source. This could cause severe damage to the inverter and is not covered under warranty.

    Info: Torque the six-connection AC terminal block screws to 16 in lbf (1.8 Nm). Torque the two AC ground terminal screws to 45 in lbf (5.1 Nm).

    The following steps are basic guidelines for installing and connecting AC wiring directly from a

    main panel into a MS-PAE Series inverter, and from the inverter directly to a sub-panel.

    Note: If you are installing the MS-PAE inverter(s) on a MMP/MP enclosure, refer to the respective enclosure owner’s manual for all AC wiring instructions (as an example, Figure 2-9 shows the AC wiring for a MS-PAE inverter installed on a MMP enclosure).

    1. Remove the two Phillips screws on the AC wiring compartment cover (Figure 1-3, Item 15) to access the internal AC terminal block.

    Wiring the Inverter AC Input (from the main panel)

    1. a) For a 120/240 VAC input: Connect the hot 1 wire (black) from the main panel’s dedicated dual-pole circuit breaker to the inverter’s HOT 1 IN terminal, and then connect the hot 2 wire (red) from the main panel’s dual-pole circuit breaker to the inverter’s AC HOT 2 IN terminal. b) For a 120 VAC input: Connect the hot wire (black) from the main panel’s dedicated dual- pole circuit breaker to the inverter’s AC HOT 1 IN or AC HOT 2 IN terminal, but NOT both or damage may occur.

      CAUTION: If using only a 120 VAC input source, you will need to turn the charge rate down to 50% using a remote control (i.e., ME-RC, ME-ARC or ME-RTR). This prevents the inverter from overheating because of a transformer imbalance when charging the battery bank and running loads from both the HOT 1 and HOT 2 outputs.

    4480W PV, MNE175DR-TR, MN Classic 150, Outback Radian GS4048A, Mate3, 51.2V 360AH nominal LiFePO4, Kohler Pro 5.2E genset.