SMB "quality..." or NOT!

Ethereal · 12-01-2008, 03:23 PM

This all started as a merepublic service announcement to new owners to check (or change) the oil in their gensets.

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There was a paragraph here that explained that what follows elaborates upon the accusations of inattention to detail I made in the genset oil thread. It was obliterated by a sysop whose name I had dared to use to identify the individual to whom I was responding. I promise to never "personally attack" anyone on this board by such provocative action as using anyone's name again. Hopefully alternatives such as "hey you" and "that dude" will be considered non-belligerent.
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Our rig was specified to have a 120 VAC system that included a shore connection (of course), a genset, and a 2800 watt inverter. The roof A/C was to be able to run from power supplied by any of these three sources, so we could air-condition our entire 24' Sprinter whether connected at a campsite (shore), driving down the road (inverter, with a high-current alternator), or out in the middle of nowhere (genset). This strategy was explained in detail to SMB before we ever put one dime down on the van or approved any design.

At delivery, I noticed an "extra" circuit breaker box wedged between the inverter and fresh water tank (under one of the dinette seats), and inquired about its purpose.

SMB: That's so the air conditioner will run.

Me: Why won't it run off a breaker in the load center?

SMB: The inverter won't let the generator start it.

Me: So what did you do to change the inverter's mind?

SMB: We put that breaker down there.

Me: So what passes through those extra breakers?

SMB: Power to the A/C.

Me: Power from what to the A/C?

SMB: The generator...uhh...to the...

Me: Can I see the wiring diagram for the van?

SMB: [blank stares]

Me: Do you have a diagram of the van's 120 volt system?

SMB: [long pause] We...have a diagram of how to wire...an RV in general.

Me: [long pause] OK, but...everything works...right? Just as specified?

SMB: Sure, sure.

This nagged at me for the rest of the checkout process, and I kept dashing out to the van to rule out things that might NOT work due to whatever "detour" was taking place inside the mystery breaker box. My third suspicion proved correct: they had wired power to the A/C from shore and genset around the inverter, so the inverter couldn't power the air conditioner.

Once I discovered this, they explained that this was because the inverter wouldn't "let" the A/C start. I voiced my (correct) suspicion that this was due to a well-documented protective function of the inverter--to interrupt power during AC under- or over-voltage conditions, and pointed out that the thresholds are easily adjustable in software. The inverter just needed to be re-configured to ignore the normal sag in voltage as the compressor motor starts.

We spent the rest of the afternoon sitting in the shop as they fuddled with temporary "test" connections, then returned the following morning so they could permanently remove their "extra breakers" and wire the coach as it should have been in the first place. With the inverter re-configured, everything worked as it should, except that the inverter (running from batteries, not just "policing" 120 VAC passing through it) would only intermittently succeed at starting the A/C compressor.

Sportsmobile shrugged this off as "oh well, whadda ya gonna do?" and even added that they have never been able to get a true sine-wave inverter to power an air conditioner. Oddly enough, their (cheaper, cruder) modified square wave units will, which was the only solution they could suggest. I pointed out that modified square wave power causes motors to run hotter and die sooner, but again, all they could do was shrug.

It was left to us, after we got home, to research the problem (many hours), locate a solution (the SUPCO SPP6), buy it ($28), and install it (30 minutes). The hardest part, by far, was identifying the solution. This is not a new issue among RVers, though (the key info came from RV.com) and a competent builder of custom RV's ought to have been a little better informed.

I say this not as a figure of speech, but literally:

The guys who built our rig did not know what they were doing!

They didn't know (despite abundant documentation) how the inverter worked, didn't know how to adjust its software settings, and apparently didn't even know (or couldn't articulate) what their Rube-Goldberg workaround had done to make the A/C "work." Like a redneck with a Crescent wrench and a case of Budweiser, they just kept flailing around under the hood until they came up with something they thought we'd drive away in.

Further, they didn't even bother to know a simple fix (the SPP6) to a problem common to many of their previous customers!

I guess it was just easier to shrug.

CJ · 12-01-2008, 09:28 PM

Workmanship = little to none
Quality Control = poor at best
Quality Assurance = low and not to assuring
Maintainability = If you want to drive a few hundred miles and pay for it.
Reliability = time will tell
customer service = niceness but my loss.

monitor this, and get the AMS oil corrective action to us soon for your basic manufacturing/assembly error.

Jammyauto · 12-02-2008, 10:51 AM

Damn I guess now I have to send my SMB to the crusher. I was pretty happy with it in general but now I guess you have changed my mind.

Ford_6L_E350 · 12-02-2008, 01:41 PM

I'm sorry you had a bad experience.

But, I don't believe that means that everything SMB does is suspect. In fact, they do very good work on their specialty - converting vans into unique campers.

And, for a standard camper they do quite well. It seems most of the issues and problems occur with specials, not standards. On any non-standard modifications, I would expect the person specifying the changes to know more about the changes than SMB would know. And, like the rest of us, they learn best by making mistakes.

And, none of that will ever excuse the mis-plumbing of a remote oil filter on a production basis. After the first couple of units, that is a standard conversion part, not a special.

But, your wiring problems are a special. Not something they normally do, or something they understand. Nor should we expect them to have an electrical expert on staff, not unless we want to pay alot more for a van conversion.

Mike

Psomaki · 12-02-2008, 03:09 PM

Mike, afraid I can't quite agree. We're very happy with our old SMB, which apparently was built right from the get-go (we have all of the documentation on it). BUT I think the bad experience that started this thread is inexcusable. I agree with your position that the SMB folks can't be expected to have every expert on hand or to know everything about every possible custom. What they CAN and SHOULD do is to tell any customer, or potential customer, when they don't know if they can effect a particular mod or custom fit. As I get it, in this case SMB accepted the order, said sure we can, later said here it is and we did it, and then had to admit what they knew all along - - that they had no idea how to do what the customer wanted. I can trust a company that knows, and admits, its limitations. I'm not so sure about one that will dissemble, as SMB appears to have done in this case.

Ethereal · 12-02-2008, 06:35 PM

I won't use any names (because, apparently, I can't), but I'm not advocating anyone take their SMB to the crusher. I'm certainly hanging on to mine. I know it doesn't show in this thread, but (of course) lots of things were done right on our van, and we're (mostly) very happy with it. SMB was very flexible, creative, and accommodating in terms of layout. Put a seat here or there, make the closet wider or narrower, put bunks over the dinette (we wanted a LOT of sleeping capacity!)...they can do it all day long, in our experience.

Where they seem to struggle is in terms of items or systems that must do something (or several things). Even this, though, isn't what really infuriated me. It was their apparent level of comfort

with their mishaps, unintended consequences, and things about which (according to them) "nothing could be done."

I also do have to disagree a bit with the notion that our 120 VAC system was all that "exceptional." Every feature we ordered was described in detail on SMB's own website. (Our particular inverter was not their standard, admittedly.) The notion of running the roof A/C, via an inverter, using power from the main engine's high-current alternator, is right there on

Sportsmobile's Own Site.

Ford_6L_E350 · 12-02-2008, 07:16 PM

Quote:

Originally Posted by Ethereal

I also do have to disagree a bit with the notion that our 120 VAC system was all that "exceptional." Every feature we ordered was described in detail on SMB's own website. (Our particular inverter was not their standard, admittedly.) The notion of running the roof A/C, via an inverter, using power from the main engine's high-current alternator, is right there on

Sportsmobile's Own Site.

You are right. It clearly says they can do it. It also says you can run the AC off the batteries for an hour or so. Sorry I didn't see that.

I know the SMB factories are all independent businesses. I don't know which one wrote the part about running the roof AC from the inverter, nor do I know where your van was built, but it shouldn't matter. If one factory doesn't know how to do it, they should either not take the order, or contact the knowledgable plant for the detailed installation instructions.

Accept my apology,

Mike

Greg In Austin · 12-02-2008, 07:41 PM

I am sorry you had a bad experience. We are very happy with our SMB.

We do not have a Sprinter, but we have an 110v system that will drive our AC for a couple of hours..... and we have a generator (that we supplied) that works with the inverter to allow that. The inverter that we spec'd did not work. The replacement inverter (same model) did not work. We went to a different model and it works great.

SMB TX worked with Danhard and Xantrex to understand why the initial model of inverter would not work. Technicians at both companies said it should be working, but it didn't. They did all this on their nickle. It also gave them the information they needed to drop the newer higher model inverter from their options, and save others from future issues.

Ethereal · 12-02-2008, 09:10 PM

Quote:

Originally Posted by Ford_6L_E350

You are right. It clearly says they can do it. It also says you can run the AC off the batteries for an hour or so.

And with the added starting capacitor, we can. Everything else works fine, including being able to run the roof A/C on nothing but battery for short stints, like cooling off after a hike.

I knew (or at least strongly suspected) that the compressor starting torque was the only hurdle to overcome. I was just dumbfounded that SMB had no interest in solving this one key problem. With the additional cap, it actually draws MORE current at the moment of startup, but the compressor spins up and drops off to just a running load before the inverter times out on the current overdraw. (That's NOT adjustable in software, to prevent smoking the MOSFETs.)

Ethereal · 12-02-2008, 09:21 PM

Quote:

Originally Posted by Greg In Austin

SMB TX worked with Danhard and Xantrex to understand why the initial model of inverter would not work. Technicians at both companies said it should be working, but it didn't. They did all this on their nickle.

Maybe they felt less responsible since we brought "our own" inverter, but that still doesn't account for their blase' attitude that the sine wave units they use won't start their A/C's either.

Again, they did a lot of things VERY well, but in some ways that makes the stuff they shrugged off even more maddening, or at least baffling. If I had been prepared for a "mostly right" product, I would have taken tools and test equipment to Austin with me, instead of my wife and two little kids.