Magnum MS4448PAE with 110v generator

TakeItEasy

A friend and I are finishing up installing a Magnum MS 4448PAE inverter charger with a small PV array. We're trying to hook up a 110V generator to the AC input to charge the batteries, but we can't get the Magnum to start charging. I've double checked the auto-connect setting and all the other AC inputs that might be keeping it from charging, and I'm not seeing anything. Also spent a few hours reading back through the manual and other threads on this forum, and we're still stuck.

Is there a trick we're missing?
Does it matter which leg we hook up the generator to?
My friend had the suggestion of splitting the generator output to both legs so that each leg would see 120, but not within 180 degrees of each other, but that didn't work.

Any help you all can offer would be much appreciated. Thanks!

Blackcherry04

Re: Magnum MS4448PAE with 110v generator

Have you verified the Output from the generator's Quality ?? 120v @ 60 hz ?? The only issue I'v ever had with Magnums is the charger will overshoot the Charger settings and kill the generator at times. But if it's not qualifying the power there generally a reason, and it can't synchronize to it.

From the Manual

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

Vic

Re: Magnum MS4448PAE with 110v generator

Hi T I E,

Welcome to the Forum.

I have NO experience with Magnum inverters, but, on page 28 and 29 of the manual, see that they show 120 VAC input only between Line 1 and Neutral. SO, appears to me that it DOES matter which hot that the a 120 VAC genset is connected to.

EDIT; I have not read the manual, looked at the specs and couple of diagrams ... So would go by what B C 04 says.

Good Luck, Vic

TakeItEasy

Re: Magnum MS4448PAE with 110v generator

Thanks for the feedback. I didn't see that warning in the manual that you pointed to, but I'll take another read and we won't try that again.

We also have a Morningstar charge controller that was trickle charging the batteries (it was cloudy and drizzly out). How does the Magnum handle the charge function when there is an external source? We installed the battery monitoring kit, so is it possible that it saw current travelling across the shunt from an external source and that is why it wasn't charging?

My problem aside, how does the Magnum handle charging when there is an external source charging the bank as well?

Thanks again

Blackcherry04

Re: Magnum MS4448PAE with 110v generator

The external source shouldn't be a problem, unless it's above the high or low voltage cut-off. Does the Inverter Invert ?? Can you hear the Transfer relay when you connect the Generator ?? It'll never charge until it accepts the incoming power.

TakeItEasy

Re: Magnum MS4448PAE with 110v generator

The inverter does invert, we can power everything in the house without a problem. We're just trying to make sure the charger function works. We haven't heard the transfer relay at all. There is voltage at the inverter input terminals that's within range, my guess is maybe it's a frequency issue? Our generator doesn't display hertz, so I guess we need to get another meter. When I change the AC input setup to disabled, the charging LED does blink, indicating that it is detecting voltage at the input terminals, but a user setting is preventing the inverter from charging. But then when I switch it back to enabled, we're right back where we started.

Still scratching our heads...

BB.

Re: Magnum MS4448PAE with 110v generator

If you do not have one yet, get a DC Current Clamp Meter so you can verify current flow in different parts of your system quickly and easily.

This one is fairly cheap (in the US, from Sears) and is "good enough" for debugging your system. It also has frequency measurements and is a full AC/DC current clamp + DMM (Digital Multi Meter). (note, I don't use the thermal probe--the plug for the probe fell apart almost immediately--But I use an IR meter for quick thermal measurements anyway).

Plus, with DC clamp meters, if you pay attention to which way you clamp onto the cable (if you "flip the meter clamp, the current flow is "reversed through the meter), you can see which direction (+/- sign on display) the current flow is in your DC circuits. So you can tell if the battery is being charged or discharged (for example) independently of any other inverter/charger/controller meter readings.

AC and DC Current Clamp Meters are much easier and safer for debugging power systems (no cutting of wires, connecting meters to live circuits, high current flow destroying meters, etc.). You just clip the meter on one wire and measure the current (zero display first for DC current meters). Very easy to check parallel current connections. If a Solar Array String or battery string is not carrying its share of the loads.

-Bill

Blackcherry04

Re: Magnum MS4448PAE with 110v generator

TakeItEasy wrote: »

. There is voltage at the inverter input terminals that's within range,...

What is that Voltage ?? You said you had a 110V generator. At 110 V output it could easily be out of the frequency range depending on the AVR if it has one. One could assume ( can get you in trouble ) if the generator was putting out 120V it would be in the 60hz range if it's working correctly.

TakeItEasy

Re: Magnum MS4448PAE with 110v generator

We're measuring 123V at the inverter input terminals, so we should be good there. We have a Mastech 2108 clamp meter that measures DC current, but having trouble figuring out if/how it measures frequency. We're running our laptops off the generators, isn't that a sign that the frequency is pretty decent?

Appreciate all the help, thanks for your time

BB.

Re: Magnum MS4448PAE with 110v generator

TakeItEasy wrote: »

We have a Mastech 2108 clamp meter that measures DC current, but having trouble figuring out if/how it measures frequency.

I did find the English Manual here:

http://www.aidetek.com/New_products_info/Datasheet/huayi/MS2108A_english_manual.pdf

The data sheet says it can measure frequency from both the Current Clamp (only when current is flowing--I would guess) and from the meter plugs.

It looks like you just set to measure frequency and either clamp the cable or use the meter leads (be careful, you may get a shock if you have meter leads connected and use the current camp--if I read the manual correctly).

There can be problems with the wave forms from various power sources (and the current wave forms from different loads)... Either you are +/- 5 Hz from the "true reading" or you may be off by 2x or more due to wave form issues (square waves, non-sine waves, etc.).

We're running our laptops off the generators, isn't that a sign that the frequency is pretty decent?

Appreciate all the help, thanks for your time

Usually not--Depending on the power supply, they can run on DC or from 50-400Hz pretty easily.

A generator with mechanical governor is probably doing pretty well if it is within +/- 2 Hz... +/- 5 Hz is not uncommon to set Inverter/Charger qualification values for (I think).

Utility line frequency is typically +/- 0.5 Hz (and, on average over ours/days/weeks) very close to +/- 0.00000 Hz (atomic clocks and all that).

-Bill

Blackcherry04

Re: Magnum MS4448PAE with 110v generator

Well, if the voltage is 123V a guess the frequency is ok. Is it a New Inverter ?? I am sure that Magnum support can find the problem.

There is one more thing I would do. Pick the Inverter on one end and raise it about 1/2 " or so off a hard surface and let it drop on to the surface. If it has a stuck relay it will unstick it. This is a known way to do one recommended by the service centers. Even if the electronics are calling for a transfer, if the relay doesn't mechanically function, it will not do it. you can do it with everything hooked up. I'd do it on each end.

SolarMusher

Re: Magnum MS4448PAE with 110v generator

Hi, it could be only that your magnum is in fault... Check your ME-ARC, go to tech, clear the faults, shut down your DC disconnect, then switch it On. Some faults don't appear on the display. Also, if your batteries are above 51.2 because of your solar, the Magnum charger will go directly to Float without charging.

Coach Dad

Re: Magnum MS4448PAE with 110v generator

There are a couple of things you need to set...

Control Setup
-01 should be set to Auto Connect
Charger Setup (part1)
-03A- AC Input AMPS = 30A
-03B- Battery Type = Custom: Absorption voltage = 28.6V, Float voltage = 26.6V, Equalization voltage 31.0V
-03C- Max Charge Rate = 100%
-03D- VAC Dropout = 80VAC

Farlander

I have a similar problem with the magnum pae4448 charging off generator.  We have a 12kw generator with 240v output.  Inverter settings are
AC Input amps: 40
Battery Type: Custom
Max Charge Rate: 20%
Max DC Charge Amps: 20

Generator gets bogged down like crazy and begins to smoke almost every time.  Overall pretty unhappy with magnum generator charging, it's pretty terrible.  Any input welcome.

just starting

If a.c. amps in is set to high for gen it will bog down. You lose 3.4% for every 1000, above sea level on any combustion engine. try to set the amps in to 30

mike95490

Do you have any way to adjust the voltage and frequency windows for the inverter/charger ?  Most generators have some frequency "wobble" and are not perfect.  I set my window 55hz - 65hz and never have trouble.
Some generators have "spikey" outputs and need a 100w lamp wired to the the same leg feeding the inverter, that helps stabilize the voltage, the charger starts up, and then you can disconnect the lamp.

Wbuffetjr1

following

Estragon

@Farlander - what kind of generator? Is the magnum wired for split phase, or just on one hot leg of the 240v output from generator?

Hill_Country

We have a Magnum MS4448PAE inverter as part of our MMP (Magnum Mini Panel) installation, along with a 110v gas inverter-generator (we have a Yamaha EF2000is) we use to charge our battery bank when needed. 

I had to use our generator for the first time last November and I had issues very similar to what other folks mention in this thread; mainly, you switch the AC Input breaker to 'on' in order to use a generator to charge the batteries using the MS4448PAE.  I found that my issue was just a couple settings within the ME-ARC menu tree.  I don't remember the exact name of the menu items, but there are two settings that affect each other.  One was the total max current (in amps) that the MS4448PAE should try and pull from the generator, and the other is a % setting for maximum charge rate for how much the Inverter/Charger (i.e the MS4448PAE) should try and sustain for charging purposes.  Since our small-ish generator can only produce about 12-13 amps sustained (60hz/120v), so I had to set this % charge rate relatively low, as well as make sure the total number of amps was below the generators threshold, so as not to over load the generator and cause it to shutoff. 

The other thing to keep in mind is that if you have a very large load (for us that would be a septic pump, for example) that is running while your generator is connected and "charging" the battery bank, it will quickly overload the generator as the Magnum will give priority to loads on the inverter over any charging of the battery even though you've set the maximum amperage.  Hope this helps!

The other thing I often find myself forgetting is the AC IN breaker on the MMP (Magnum Mini Panel) is actually set to ON   I can't tell you how many times I've scratched my head wondering why the MS4448PAE never acknowledges the generator and realize that the AC IN breaker is not ON.

Farlander

It's a caterpillar 12kw diesel, portable style gen set.  Probably weighs about 275 lbs.  Not sure the model.  Yes I am told output is 240V split phase (3 wire + ground).  Generator was initially used with 120V cord by someone inexperienced and apparently generator smoked, my have damaged it?  We have upgraded the cord feeding the inverter.  Another possible issue is this off grid site has 3 refrigerators and a couple 1/2 horsepower 120V water pumps that may be mostly or all on the same AC leg.  I think this is contributing to the generator loading issue.

We have adjusted the AC Voltage Dropout up from 80V to 100V. This has helped prevent serious bogging when pumps and other inductive loads kick on and allows the inverter time to recalculate battery charging.  The inverter automatically reconnects to the Gen once the load has stabilized.

I never knew the magnum would go direct to float above 51.2V.  Not a good design for our batteries, which float at 52.8V at the low end.  We have since raised the float to 55.2 on the inverter only to try and improve charging, however the 2 charge controllers handling the 6kw PV output are in bulk charge at 57.6.  It would seem to me that if the generator is run when the chargers are in their bulk stage and above 55.2, then the generator will not do anything to assist in charging, correct?

Estragon

The good news is diesels tend to take a fair bit of abuse as long as you stay on top of oil changes etc. Loading everything on one side of the split phase could certainly be an issue. The generator should easily handle 9-10kw of balanced sustained load - in fact it will likely be happier that way than lightly loaded. Running it with, say, 4kw all on one phase will not make it happy. If the smoke is black, getting the load balanced and running it at around 75% of capacity may help a lot. Give it a warm-up period for the engine, and a cool-down for the alternator though. If the smoke is blue or white, you may have a bigger issue.

Like Hill_Country noted, my outbacks have a couple of setting that affect charging versus loads. You might want to review how these are set on your magnum.

I'm not familiar with magnum settings, but there should be an absorb voltage setting, which you would want to set to the same voltage and temp comp as the charge controllers. There should be two different settings; one for absorb voltage, and another for float voltage. Realistically, you wouldn't be floating a bank with the generator anyway, so that voltage shouldn't really matter. The absorb voltage is the one that matters.

Typically, we would use the generator to bulk charge the bank in the morning to around absorb voltage (eg 58v) then turn off the generator and let whatever pv power we get finish absorb as much as possible.