Magnum no longer supports series stacking on MS4024 - at all. No support.

[Droo71]

Just a warning for anyone on 24V systems about feature support - and also, I suppose, a commentary on what I keep reading is a company with 'great tech support'.

I purchased an MS4024 a few years back for an offgrid property. Works great. This year, I turned out to have an *occasional* need for 120/240AC - and my MS4024 is *not* a PAE model, so it only does 120.

But a bit of research -- right here on the Magnum site, shows me this : https://www.magnum-dimensions.com/se...king-interface
Its right in the list of accessories. So I downloaded the manual and install instructions. Same for the current manuals for the MS4024, MPSL-60S, MP-D backplate, MPXS extension module, ME-ARC remote.. Informed purchasing. Bought all the equipment and necessary upgrades... --another MS4024, and added in an MPSL-60S, MPXS extension module, a Backplate, and an additional ME-ARC......
.
Got it all installed. Connected up the cables as indicated in the manuals - the remote throws a 'Stack Clock Fault' error. No amount of resetting or following the manuals fixes this - and the inverters shut off when it happens. (Ok, i appreciate the safety mechanism - but what do I do NOW?)

When I get a response from Magnum support, it is basically this: 'We removed support from this stacking feature in Rev. 6.0 of the MS4024 inverters. No, we realize we didn't update that information on the website or in any of the current manuals, nor is there a bulletin posted'. The tech can offer me no suggestions on workarounds. No offer to or willingness to change out my 6.0 control board for a 5.5 or 5.4 rev which still has the feature. Quite literally, the end of my response from Magnum tech support is:

"The MS4024 is only a 120 VAC inverter/charger. The inverter you needed was the MS4024PAE which is stackable and is a 120/240 VAC inverter charger. Sorry about the bad news."

That's actually a cut-paste. I asked if they would exchange, or sell, a functional control board - no response *at all*. Just silence. Also the tech seems *unaware* that for over a decade, you could series-stack MS4024 units, that *two* of them will share a neutral with a stack cable and provide 240. (in fact, this seems to be the ONLY purpose for the red-labelled stack port on the MS series of inverters).

You know, I read a lot about how awesome tech support is at Magnum. I like the equipment - but as you can imagine, I'm not impressed.

I'm particularly not impressed that the ME-SSI is still listed on their site as a series-stacking option, and the *currently downloadable* manual for the MS4024 still indicates that series stacking is a feature. My choice per Magnum is 'Buy MS4024PAE units'. It's a bit late now.... selling a pair of MS4024s with the primary feature that you would buy two for *disabled in firmware* is a huge loss.

I'm furious, admittedly -- but also annoyed that now - as I can afford to because these 'high quality inverter' systems aren't cheap - I"m going to have to move to another manufacturer. I certainly won't invest more money in Magnum equipment after having had this happen.

(and of course, I have no real recourse, because I'm in Canada, and Magnum isn't.)

[Mike90250]

Wow, that a bummer. I know of no workaround

[Droo71]

I actually think its a bigger deal than 'a bummer'. They are *still* advertising the ME-SSI stacking kit to series-stack MS4024 inverters on their website - but this is not a function that exists in their software -- and their support refuses to stand behind it.
I'm not in the USA, but I'd be at the FTC already if I was.

I've always heard how great their support is and how they stand behind their product -- but wow, this is a cop-out.
I found a place where I can buy a version 5.4 control board, so I think I'm going to do that and replace it myself -- but it will certainly be the last Magnum/Sensata purchase I make. We are going to need another charge controller, and I was looking at stacking PT-100s , but I am thinking of switching to Midnites instead, now..

I'm quite gobsmacked that tech support refuses to stand behind a feature that's over a decade old that they still advertise and haven't removed from *any* of their current documentation.

I don't think the product is any poorer - but tech support certainly is. I suspect there are some ownership changes to blame.

I was also surprised to find out that in their panel enclosures, they only have a big enough connection from the BAT+ and BAT- busbars to support a single MPPT charger. The busbars and connections are current limited to 125A -- ( two PT100s will push 200A )-- and they have no provisioning for accomodating a larger array. (~2700W at 24V, or 5400W at 48V, are your maxes with a single PT100) .. When I emailed tech support for options, they simply said 'Nope. limited to 125A. that's it'

There *are* options. You can put 3rd party busbars in the panel. There is room on the DC- plate above the shunt for additional studs. I ended up adding an Outbakc FW-BUS plate with studs drilled in the right places onto the bottom of my breaker extensions, giving me 3 3/8, and 4 5/16 studs to work with -- but the lack of effort/response for someone who's invested fully in their product ecosystem, well -- that's disturbing.

And I guess it should be food for thought for anyone else looking at Sensata/Magnum products.

[RV10flyer]

I think if most of us go above 3000W inverter, we go up from 12V to 24V, If going above 4000W, most of us go to 48V. Still, they should have announced this on their website and these forums. It cost them nothing. I’m sure there are few customers that this would apply to, but we are seeing poorer customer service all over the world now. It’s really sad.

[Droo71]

I'm on 24V , with a 4000W inverter. I don't need an added 4000W -- I need the 120/240V . Since I already owned all Magnum stuff and the series stack was advertised -- simply stacking the second inverter was the simplest, most cost effective option.

I don't need more power. But I will eventually - so this was a *good* option. I mean, its their right to stop offering features when it suits them - but how you manage that , and not screwing over already invested customers -- those seem important to me.

[Droo71]

As an update for anyone reading -- I went to ebay, and bought an old stock new-in-box MS-4024 Control Board. $300 USD.
Firmware is 5.4 - installed it this morning - works flawlessly. Nothing in the inverter hardware that prevents this from working -- although I"m quite cranky that Magnum wouldn't help me and I had to research this and find and purchase the solution *myself*.

This isn't a 'hardware support' issue. This is 'they don't want to do the MS4024 anymore. If you want to stack, go buy the MS4024-PAE and the expensive router'. Both my inverters are under 3 years old. This *SHOULD* have been warranty support.
It should *especially* have been warranty support, since they are *STILL* advertising that the stacking kit supports 240V on a pair of MS-4024s on the Magnum-dimensions websites.

I asked about an old firmware card, and got silence. Literally a month of no response from the support tech. I'm not in the USA, but really think that it seems that management at Sensata isn't up to speed on this. I *suspect* it qualifies as misleading advertising/product mispresentation , since the 'this feature still works' documentaiton is all still up, over a month after my initial complaint to them.