Very Old APC UPS 1200 VX Manual

[UnexpectedBill_apc]

This was originally posted on APC forums on 11/18/2015

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I have a very old, but still quite functional, APC 1200 VX model uninterruptible power supply. It is from the early 1990s. I would like to obtain an owner's manual for this unit, but I did not find one available for download anywhere on the APC web site. Also useful would be any information regarding its communication capability. While it has a communication port, I'm unsure if it uses the "smart" or "simple" signaling protocol...or even something else, considering its age!

If the manual in question is only available in something like paper form, I am more than willing to pay for a copy.

[BillP]

This reply was originally posted by Angela on APC forums on 11/20/2015

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Hello,

Do you have a picture of your unit? 

The only thing I could find from this era for you was what we call the Second Generation (2G) Smart-UPS - is this a Smart-UPS or Back-UPS? I don't see any VX mentioned here but I also did not read the whole thing admittedly. I know we used to have VS though which I think is covered in the doc I'll attach here for you to review.

[UnexpectedBill_apc]

This was originally posted on APC forums on 11/24/2015

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At this time, I don't have a picture. I'm working to get one and hope to have it posted here soon.

What I can tell you upon further examination of the unit is that it dates from late 1987 (around the 40th week, based on date codes inside the unit). It still works perfectly well in every way, and is in excellent condition for its age. I can't even imagine how many times the batteries were replaced!

I was able to find some old magazine advertisements from APC that suggested these units were marketed until sometime around 1993 or 1994. There appears to have been a very closely related 850 VA model. It's definitely not a member of the "2G" product family that you mentioned.

Years ago, provided my memory can be trusted, American Power Conversion used to tout the "legendary reliability" of their products and encouraged reports from people with an old unit that was still chugging along. This one certainly qualifies! Is there still such a program in effect at APC these days?

[UnexpectedBill_apc]

This was originally posted on APC forums on 12/7/2015

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Here are some pictures of the unit.

As previously mentioned, it still seems to work quite well. Any information that's available would certainly be appreciated. Anyone wanting larger pictures can find them here: http://greyghost.mooo.com/apc1200vx/

[BillP · Accepted solution]

This reply was originally posted by Angela on APC forums on 12/7/2015

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Hi William,

Wow, yes it is an old unit. I can't find any information on those unfortunately. I think we have one of those here in our display case showing APC's history  As it is, the guide I did find for the 2G units was a scanned version of a paper copy someone had done a while back.

If you wanted to share your experience with this older unit, I don't know if we have a "program" but I often see these types of stories shared through our Facebook or Twitter pages. If you don't have those social media accounts, esupport@apcc.com works too for email. They may also have additional information on the unit or be able to get it but I doubt it due to the age  and because it has been so long.. 

[voidstar_apc · Accepted solution]

This was originally posted on APC forums on 12/8/2015

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Hi William,

One of APC's founders, Manny Landsman, is a big fan of the old stuff. He found some documentation in our archives which I've sent you via email. As for communication, try UPSLink and see if it responds to Y at 2400/8/N/1 with a 940-0024 cable. If not, then it's probably simple-signaling only.

[UnexpectedBill_apc · Accepted solution]

This was originally posted on APC forums on 12/8/2015

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I just checked my e-mail and...WOW! That is so much more information than I expected! I'd like to take a moment and thank everyone who went to the trouble of responding, looking stuff up, digitizing it and passing it on to me.

I haven't tried to communicate with the unit using any kind of cable just yet. The documentation appears to indicate simple signaling capability only.

[Islander_apc]

This was originally posted on APC forums on 3/27/2016

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I have 3 of these UPS in various states of repair (one working 2 with niggly faults). I find them useful as an inverter for a 24v solar installation as their cost is good (free) and they are smart enough but not too clever ie. they will run with only 24v applied.

I would be very interested in any documentation available for this generation of UPS that would enable me to repair and enhance the ones I have.

[UnexpectedBill_apc]

This was originally posted on APC forums on 3/27/2016

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If it helps, all of the Smart-UPS models are cold start capable, which is to say that they too can be operated only from a battery supply for as long as the batteries hold out.

For the units you've got with problems, I'd look in two places: aged electrolytic capacitors that have drifted out of tolerance and potentially welded or burned relays. These are easily the most common failures with any of these units, and the 1200VX is definitely old enough that some of these things are reaching their lifetime limits.

Hopefully someone from APC can better help you, same as they did for me.

As a very late addendum to all of this, I would have loved to see the display case of APC's history that was mentioned earlier. I'd love to know what their very first UPS products looked like, or even what they would have been called. I've never seen anything older than the 1200VX.

[RFI-EMI-GUY_apc]

This was originally posted on APC forums on 5/12/2016

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voidstar; I have exactly same unit as William and it has a 1989 date code. (SN P891110912) I could also use the documentation for this unit. I am right now trying to decide whether to replace the batteries a fourth time. Honestly, it looks like this guy is going to be running well into its 30's on a new set of batteries.

What I like about it:

1) The extended run time.

2) can be turned on and off independent of utility power. I can finish my work, turn it off, then come back and turn it back on to use the computer (and other stuff) while the utility power is still out.

3) The clean power it delivers.

4) It is built like a tank!

Could you please forward to me a copy of whatever Manny Landsman was able to dig from the archives? Thank you!

On 12/8/2015 5:11 PM, voidstar said:

Hi William,

One of APC's founders, Manny Landsman, is a big fan of the old stuff. He found some documentation in our archives which I've sent you via email. As for communication, try UPSLink and see if it responds to Y at 2400/8/N/1 with a 940-0024 cable. If not, then it's probably simple-signaling only.

[KenKoehler_apc]

This was originally posted on APC forums on 8/15/2016

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Interesting to find more old timers like me and my 1200 VX.

1) What did you decide, to replace the UPS or keep it and replace the batteries?

2) If you replaced them did it work out good ar bad?

3) Did you ever get emailed any documentation? Mine got lost before Taylor Swift was born.

Mine might have a little more than normal life in it. When it was new it ran for a year or two then was put in storage 8-10 years. When the company folded I got it lovingly replaced the batteries it's still running today. I don't recall but I think the current useless battery is the 3rd.
Regarding age and capacitor life is it effectively 30 years old or 20 since it wasn't powered up for 10?

I appreciate any help in making my decision whether to pull the plug for the last time or buy batteries. I guess that assumes I can find them still. 

[UnexpectedBill_apc]

This was originally posted on APC forums on 8/15/2016

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On 8/15/2016 12:29 PM, Ken said:

3) Did you ever get emailed any documentation? Mine got lost before Taylor Swift was born.

The folks at APC were able to provide me with documentation concerning the 1200VX UPS. Perhaps this thread is still on their radar. Unfortunately they will have to be the ones to provide this documentation.

The APC 1200VX UPS I've got now is still chugging along. It shows no sign whatsoever of stopping. The batteries are still quite readily available, though it's a bit involved to change them unlike their later models.

Whether the unit is in use or not, its components are still aging. For many things this simply doesn't matter. A properly made transistor or microcontroller ought to go on working for many decades if properly made and employed. The only obvious bugbear I see is that of electrolytic capacitors drying out over time and drifting in value. Those can certainly be replaced if need be. It's likely the small ones that will dry out and fail first. (Electrolytic capacitors that are stored for a long period of time without use can become faulty, as I found when I discovered a still-new-in-box second generation Smart UPS 600. After a few uses, though, its capacitors "reformed' themselves and it has been working flawlessly.)

Personally, I'd replace the batteries and run the unit for as long as it's willing to go. Mine's almost thirty years old and I'd not be at all surprised to find that with a little care, it might make 40.

If you decide that you no longer want your 1200VX, I might be interested in it (so long as it's a 120 volt model and you're somewhere within the US).

[KenKoehler_apc]

This was originally posted on APC forums on 8/16/2016

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I have replaced the batteries in it before so that part doesn't bother me. Well that spark when you connect to the terminal does but it won't stop me.
Replacement batteries are still like $130. Risking that gives me pause. 

I've determined my choices are:
- Risk the $130.
- Send it to you. It should have a good home. BTW I'm in Ohio.

Thinking out loud: 
I've got whole house generator now so the extended run time is less critical.
I've got several SMT-15000's used off eBay so the need & risk to keep this one going is less pressing.
I guess I'm leaning toward letting it go. I'll be more comfortable making a decision in a day or two once I'm confident the 2 SMT-1500's I just got are stable. One was flakey initially but after letting it charge & calibrate batteries it seems OK; passes self test.

[UnexpectedBill_apc]

This was originally posted on APC forums on 8/16/2016

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Yeah, that big spark makes me nervous, but at least I know it's coming.

If you do decide to let your 1200VX go, just shoot me an e-mail. (The pictures I linked above come from my personal web server, where you can also find contact details. I say that only because I don't know if APC/Schneider Electric has a prohibition on posting an e-mail address here.) I'm located in Illinois.

[KenKoehler_apc]

This was originally posted on APC forums on 8/18/2016

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I just sent you an email.
More news in a few days.

[dherman_apc]

This was originally posted on APC forums on 10/31/2016

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I am also looking for the manual to our old but still functional APC 1200 VX.  I would greatly appreciate it if you can forward me a copy of the documentation that Manny Landsman found.

Thanks,

Dave 

[BillP]

This reply was originally posted by Wolf on APC forums on 4/22/2017

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Bumping this, because I also encountered this very old model, and would greatly appreciate the documentation for it. Mine is a 230V version made in 1990. Seeing how several people already indicated that they need it, perhaps someone will be so kind to upload the information somewhere. Thanks in advance.

[popauld_apc]

This was originally posted on APC forums on 2/14/2019

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Hi, Voidstar.  I hope you're still around.  I just discovered this forum.  I have a vintage 1990 (s/n P900804390) still going strong. I am an electronics engineer, and into power quality and auditing. My 1200 VX is extremely sensitive to power dips and surges, which most times I don't notice.  It's because of its beeping that I know something happened and it kicked in to protect all my sensitive stuff.  I ran a power failure test to take an oscillograph of the output.  The transfer to battery power was almost instantaneous, and the electronics follows the commercial power so that the inverter control is synchronized to the commercial source, making the transfer undetectable; well less than the ¼-cycle typical of an electromechanical relay.  I did have one problem.  On Sundays, when power consumption in my (home) area is lower, the utility voltage tends to rise, at least earlier in the morning.  So the UPS would kick in on battery power.  I studied the control board, and discovered several adjustments.  Further study led me to identify the threshold adjustment, so I was able to tweak the sensitivity.  I would love to get my hands on a schematic, and from the forum posts, you would seem to be a good source.  And at least for the info you emailed to others some years back.  Sorry this is so long, but I am that interested.  Here is the waveform capture at the moment the commercial power was interrupted; transfer approx 2.6ms:

[tcharron_apc]

This was originally posted on APC forums on 10/6/2019

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I have an 800 RT from 1989 that is still chugging along.

I really like this unit as it generates a nice sine wave output -- all of the other units I have tried generate stepped square wave outputs.

Does anyone have manuals that they can share with me for this, or the 1200 VX?

Thanks

Tim

[UnexpectedBill_apc]

This was originally posted on APC forums on 10/7/2019

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Evidently there are many more of these out there today than I'd have ever guessed. When I first inquired, the folks at APC were very helpful. I'd have to think that this thread is still on their radar, and hopefully they will help you out.

For when that time does come (even though I think it'll be a very long time), the 750VA and larger SmartUPS line is probably what you want. Those have a true sine wave output characteristic and are very readily available on the secondhand market so long as you're OK with a used model.

[whawk_apc · Accepted solution]

This was originally posted on APC forums on 5/3/2020

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whawk: I have a 1980 unit and would like an email containing the information found on the 1200vx or a location I could download it from. This is a great unit.

[as400jockey]

Did anyone identify a way to turn down the sensitivity on the APC 1200VX?  I have 6 or 8 of these and they are workhorses.  I've had them for over 20 years.  I've replaced the batteries many times over the decades.  But when I have to cut over to generator power, they get finicky and switch to battery at least once a minute, especially while the servers are booting up.

I have tried using a power conditioner (a hospital grade unit, not just a 'brownout' voltage adjuster) but it's still finicky.

These have such great battery capacity that I'd hate to have to toss them and get something else.

Thanks.

DAVE

[as400jockey]

Just to follow up ...

I opened up one of my older "BackUPS 1200VX" units.  On one of the circuit boards are four variable resistors - R1 thru R4.

Anyone have any insight into the functions of those four resistors?  Is one or more of them related to sensitivity?

Thanks.

[Shaun]

Hi,

I've asked someone who believes they should have some information on this unit - unfortunately the information is still on paper, in the office, and most of us are at home at the moment - so it may be next week sometime before they have a chance to check.

Just to let you know it's not falling on deaf ears - it's just taking us a bit of time as we're looking for ring-binders instead of databases.

[as400jockey]

Thanks for that.  Glad to hear that people are still watching these older threads.

I look forward to learning more.  These UPSs have done great work for me.

Thanks again.

[Shaun]

Hi Dave,

I'm not sure how much I can share of what I got back - I was expecting manuals, I received schematics.  On one hand engineering documents are usually a big red no, on the other hand, they're 30 years old and any patents have expired.  But I don't want to get your hopes up there - it's usually very easy to find someone who can say no, and very difficult to find someone who can say yes.

I don't see any pots in the AC line fail loop though, it's just compared against a reference sine.  Changing the reference signal would allow it to be mutated for 230V, 50Hz, etc, but I don't see anything we could modify to change how they're compared (short of replacing fixed-value components, which is way out of my league).

For the four pots you've found, they're labelled VR1: I Balance, VR2: I Limit, VR3: Output Volts and VR4: Xfer Level.  I make no promise as to what any of them actually do - most the signals marked (letter) I appear to be related to the inverter, and the Xfer level is on the DC side not the AC signal, so I'm not clear what level or what it's transferring.

My hunt for manuals continues ...

[as400jockey]

Very interesting stuff... Thanks again for your research.

VR4 Transfer Level sounds promising...

Curious your comment "...it's just compared against a reference sine..."

So it sounds like 2 things can trigger this thing to go on battery - low voltage or lousy sine wave?

The low voltage thing - I had a years long battle with the electric company as I was getting 110 on one leg and 108 on the other, and paying for 2 x 120 .  Got nowhere until I found a guy in the bucket truck and invited him to bring his meter.  "Huh.  That's not right... you need your own transformer on your pole".

And that's how you get it done with the electric company - find the guy with the tool belt.

But while the voltage was low, these things would cut over to battery a lot.  Burned through many expensive batteries before I got my very own can all to myself.

In this scenario, during a blackout I'm on a Home Depot Coleman generator circa "just before Y2K".  When on generator, the input voltage is OK unless the well pump kicks in, but still these things keep popping on battery.  And when one cuts onto or off battery, the voltage change or phase change seems to be nudging one of the others onto battery.  Could be a spike or drop on voltage, or could be a brief phase change making for a lousy sine wave, and then the ping-pong starts.  I don't have an oscilloscope, so I don't know how dirty the generator power is, and the 'hospital grade power conditioner' I have doesn't seem to help.  

the power conditioner I have is 220v, and I have the output wired up as two 120s with a shared 'common'.  I have one ups on one leg, the other on the other leg.

I also have a Variac, so maybe I tinker with VR4 and the variac to see where it kicks in and out.

Any thoughts on whether it has a too-high-input-voltage cutover to battery or just low voltage?

Thanks again.