View Full Version : Epilog Power supply

Graham Symns
07-30-2010, 12:04 AM
I was reading some back postings regarding the above topic.
It was on P.200 from James Stokes dated 06-17-2008.
My supplies (2) both died at the same time.The part number and model are exactly as quoted in the posting and I repeat them here:
Model :......VS1-D9-03
Astec P/N:..73-180-0579CE
I have stripped both AC/DC units to find the same 3 parts cooked.
I have competence in electronics but really would like some advice..I'm a bit un-certain as to the failure cause so am a bit wary
about just re-placing the bits and applying power even only to one unit at a time.

So in the first instance I'm wondering as to the outcome that James experienced.

Secondly is there anyone who has acquired the schematics for this power supply?

I currently have an enquiry in to Dan Phetn at Epilog, but our time difference delays things a tad.

Any comments would be appreciated.

Regards Graham Symns

andrew zen
07-30-2010, 5:15 AM
I know that power supply. They are modular with an AC/DC converter going from 110/220 AC to 300+ vDC and then another converts 300+ VDC to 48V DC at 25-30 Amps. Each module has a green light. If the module closes to the wall which is bolted onto the laser is red then the DC/DC converter is bad.

This power supply is more of a Synrad restriction than an Epilog thing. When I thought I had problems with mine I got the feeling that Epilog wanted this thing to go away. I really think Epilog doesn't want to be in the power supply business and these have probably plagued them wuite a bit. However Synrad speced the Astecs and Epilog used the Synrads.

Astec got sold to Emerson power. Astec never released schematics and they are notorious for not doing so.

There are smart people out there that will repair these things for anywhere from $250 to $400 and offer a warranty of 3 to 6 months. These repair shops fix all power supplies. I almost paid a local guy to do it as power supplies are pretty much the same and a capacitor is usually the thing that goes bad anyways. An ESR test uncovers that in 20 minutes. Easy money for them.

When I opened mine up, I saw several colored markers having dots on each capacitor, transistor and diode as a technician tested each one a couple times earlier.

The technician I took mine to said a blown cap or diode weakens other components in the circuit in his opinion. Since the price was the same to replace one cap by him or all 18 I believed him. Just be careful of the capacitor polarity and diode direction. Say a prayer before turning on
The 03 in VS1-D9-03 means the power supply will apply power to the terminals even without any pins on the 10 pins connector set high. If the green light comes on, 48 VDC is being output.
I always have a good CO2 extinguisher present in case of blowout.

You can contact Emerson directly for repair( I have attached an RMA form)
US RMA repair is in the So California.
Here is a support person's email

She is located in the Philippines. They have a fixed rate of $249 to fix them and a 60 day warranty.

I also bought a spare power supply for my 70W Legend.
It is a Lambda with he same voltage and power ratings (and terminal).
This is new old stock. Lamba posts schematics. Just have to figure out how to mount it to the metal backing in the Epilog. Shouldn't be too difficult..


They had some Astecs 48V VS1 there last month for $60 a piece, I should have bought them out, someone else did.

Ebay has some 48V 1500 W power supplies as well I also bought a Tectrol for $60. The high power is a problem. 48V is standard for DC power supplies for computer racks.

Now after thinking about it, you probably have a cable linking the 10 pin connectors between the two power supplies as you have the 100 W laser.
This connection tells the supplies when to apply the output to the terminal so that they are in sync to deliver the current needed. That is an Astec specific thing.

Good luck, you are definitely about to learn about the the dark underworld of high power 48V power supplies.

Dan Hintz
07-30-2010, 6:03 AM

One of the best, info-filled responses I've seen from a newbie in many years... virtual star for you :)

andrew zen
07-30-2010, 7:33 AM
Thanks, I spent some time on this issue.

Also, check to see if both green LEDs com on when you disconnect the laser and the other connectors from the terminals. Or course you have to keep the connectors coming from the breakers connected - that is your power.

I found that if the motherboard or anything else it is connected to has a short, it takes the power supply down with it and the power supply cycles through, turning on and off which is what it is supposed to do.

paul mott
07-30-2010, 7:46 AM

I think you have just become the resident PSU expert. ;)


Steve Clarkson
07-30-2010, 9:45 AM
I just had the pleasure of replacing the power supply on my less than 2 year old Epilog Mini........along with the X-axis motor (twice) and the air assist tube........hopefully, that will solve my problems. Can't wait for when its time to replace the motherboard and control panel. It's been a fun two weeks.......

I will once again compliment the Epilog Tech Support though.

Graham Symns
07-30-2010, 5:24 PM
Hi all,
Thanks for your replies.
I agree with Dan's comment about Andrew's credentials in his excellent response.
I did visit the supplier Andrew mentioned and spotted a likely candidate,namely the PS(LF-48-48) at USD319 / ea
As I said in my post I do have electronic experience and located the obviously impacted devices, removed them,identical parts in each supply,and have bought in named replacement parts but I am hesitant to just install (and pray).
The other big thing is the cost of freight..USD80 for a post of less than 2 ounces to New Zealand plus NZ customs etc.Very rapid delivery however.
If successful I might advertise as the New Zealand repair agent for these supplies!(tongue in cheek).
So the quest for schematics is very powerfully driven.
So please keep looking people ..maybe we can crack this annoying situation
Regards Graham

andrew zen
07-30-2010, 5:29 PM
Here is a potential replacement on ebay.

Located in Philippines.

Graham Symns
07-30-2010, 5:40 PM
Hi Andrew,

It's 9:35 AM here ..what is is your local time?
I had a look at the e_Bay site ..that sure is an attractive price ,no doubt about that.
It gives me a back-up course of action if fitting the parts and praying fails.
Thanks for that information

Regards Graham

Graham Symns
08-01-2010, 5:13 PM
Hi Andrew,
I was just wondering if you had any progress to report in fitting your Lambda replacement power supply.
If you have I would appreciate pics and any comments as to what to look out for.
I have been beavering away trying to source old/new supplies on e-bay,advice,schematics but so far nothing to add to what you so kindly have contributed.
Anyway I have been looking a little further into the DC-DC converter and see all sorts of engraver exhaust products which have got into this unit.
Hardware has rusted and a film of the goo has accumulated inside this unit,not a gross amount but enough to inspect further before I try powering them up.
The extent of the invasion is hard to evaluate until I strip this unit down so watch this space as I will report back as to what I find.
Regards Graham

andrew zen
08-01-2010, 11:25 PM
In the end, I found out that my power supply wasn't bad, but the laser display had a short, pulling down the supply.

So, I am still using my Astec.

I don't know what to say. This is all about your appetite for risk and your pocket book.

I research this and wasted weeks of my life, there is no cheap alternative for this power supply. I don;t think you are in the power supply business yourself. I see you are asking help on other forums and maybe they will help but everyone is always hoping their power supply doesn't fail because it is expensive and everyone faces the music.

I think you have a Synrad Firestar 100W or greater. You need 40A. The manual has two power supplies bridge with the communication link to turn on both supplies at the same time. Without that link, if one supply turns on and the other hasn't yet, the current goes into the other supply and that is a problem.


page 13.

They might be using Power One supplies that have been rebranded after the Astecs.

So the Lamba is not for you.

Repairing at Emerson this time seems like the best option.
having two supplies fail at once is suspicious.

The business side of me says that if you have a 100W laser. $500 US repair for two power supplies is a low percentage cost of business.

I would buy extras when you can.

Graham Symns
08-04-2010, 5:26 AM
As promised this post is to give a progress report.
Having not been able to obtain any further manufacturer documentation
I have had to trust to luck that the only failed devices were the obvious ones.
So I replaced the obviously ruptured devices after having cleaned the circuit boards and inspected them closely for dry joints,arcing & track marks.
No dry joints,arcing or track marks were found.
A fair amount of deposited grime was cleaned off.
I reinstated one PSU into the chassis and tested this outside the engraver.To my relief it powered up normally with the DC measuring 48v.
Installation in the engraver allowed the engraver to power up normally with the requsite homing of the x-y axis etc.
The engraver is now functioning normally and I now am about to do the laser beam alignment.
I hope this is of some interest but I must say I am still bemused by the fact that 2 supplies had identical faied devices,something I have not encountered in my working life.
Thanks to all who have responded.

Regards Graham

Bill Jermyn
08-04-2010, 7:19 AM
Maybe a power surge?

andrew zen
08-04-2010, 1:29 PM
Great job.

Did you take pictures of the devices so we can see the damage?

You are now the resident PSU repair person.

I hope your PSUs last a long time.

Now search this forum for power conditioner advice :)

I have an unpredictable power source here, so I bought a Ferrups UPS unit.
Power is conditioned before used.

Graham Symns
08-04-2010, 5:52 PM
Thanks for your continuing interest and no I had not thought of including pictures so I thought that I would give it a try.
So the first picture is a view is of the local area of the destroyed parts while the second is a longer distance shot of the AC-DC converter.
I should say that I have re-commissioned only one supply but I must say that I feel a little more confident now.
The interesting thing was that no track work was destroyed ..a bit of a bonus really.



andrew zen
08-05-2010, 12:38 PM
Was Q9 the failing component?

Q9 looks like a power transistor connected to the heat sink. This things can be expensive. Actually almost everything except for the caps, resistors, and diodes are expensive in this supplies. Can you take a picture of it by itself so we can see how you identified it as the cause?

I think most of us are worried about power supply issues (or should be).

Did the power supply fail during use or did it just not turn on or did it turn on and then you heard a pop and smelled electrical parts burning?

Graham Symns
08-05-2010, 5:56 PM
I have included a picture of the two failed devices.Photography is not my strong suit but I think that you can see that the failure mode is quite plain.
On the the left is Q8(the signal transistor) and on the right is Q9(the mosfet device).The part numbers are 2MPS2222 and IRF820 respectively.
Not shown is the resistor R62 ( 5.1kohms 0.6W watt).
As it happens these were available locally at several dollars each..not expensive at all, the mosfets that is.
A few seconds after switch-on the fans in the power supply came on followed by the control panel display lighting up and at this point there was a loud crack and everything died so to speak.
I found that the garage supply circuit breaker had popped.(20Amp.)
At this point I decided that the immediately obvious source of the noise was the 48 volt power supply.
So I started stripping down the supplies ,both of them, and found the above devices failed in both the supplies.
I have yet to test the second unit .The first unit has been installed ,is producing 48Volts (no bangs!) and I am aligning the laser beam optics at present.
Hope that this is of interest.


Regards Graham

Dan Hintz
08-06-2010, 7:24 AM
The 2222 is a standard signal switching transistor, probably one of the most common over the last 20-30 years. I use them extensively in my own products, and versions are manufactured by quite a few companies.

The 820 is also manufactured by quite a few companies, though I don't use those nearly as much. Nothing fancy schmancy about it, just a N-channel FET good for a few amps.

Both could be replaced by a multitude of similar devices, though I doubt you'd have any trouble finding these units again.

James Stokes
08-06-2010, 12:36 PM
On mine, I had the power supplies rebuilt, installed them and the mother board was blown. I was told that was what took out the power supplies.

Graham Symns
08-06-2010, 5:22 PM
Hi James
I have to say that I think that in retrospect I was lucky the the fault seemed to be confined to the power supplies.
As I said before I had never encountered an image fault in twinned equipment.
Sorry about your experience though.

Graham Symns
08-07-2010, 10:46 PM
I re-read your posts particularly the reference to ESR measurement.
I have done a bit more research and have found the Blue ESR meter which had its origins in a Silicon Chip magazine of 2004.
In the text for the Dick Smith kitset there is reference to the fact that that the ESR is at its worst when the capacitors are cold.
My second supply has not been re-tried for the reason that I felt that some capacitors had slighlty domed tops leaving me apprehesive about powering this supply.
I am in the process of acquiring the Blue ESR meter from Australia so as to test them.
I'll keep you posted as to the test results.
I figure it is worth it to me to be able to fix my own gear when I can.

Dan Hintz
08-08-2010, 7:29 AM

As with almost all resistances (ignoring NTC items), ESR increases with temperature, so it's at its worst at high temperatures, not low. I'm not familiar with this Dick Smith you mentioned.

If the caps have domed tops, their electrolyte has already boiled at some point... most likely over a period of time, which means those caps are probably pretty dry at this point. Time to replace them. Without the smoothing capabilities of the caps, components further down the line will suffer greatly and eventually pop themselves.

AL Ursich
08-08-2010, 12:35 PM
Bad Caps.... http://www.badcaps.net/forum/index.php?


Graham Symns
08-08-2010, 7:07 PM
Hi Dan,
Nice to have your input.
The Dick Smith I referred is an Australian icon in the consumer electronics field who marketed the ESR kitset designed by Bob Parker (also an Australian).The Blue ESR meter marketing was subsequently undertaken by Anatek,a Portugese outfit.
It was in the Assembly Manual for the ESR Meter MK2 for the Dick Smith kit Cat No.K7214 that the remark about the "ESR increasing rapidly as the temperature drops" was taken.
I have done some more research regarding this characteristic and the only source I found regarding ESR rising with temperature was from "Radio Electronics.com" which I would be think to be quite authoritative.
To be honest I am now left uncertain as to which is the absolute truth in this matter.
I rather favoured the increase with cooling as this might explain why my supplies, which were in a quite cold(our winter) workshop, failed at switch-on so catastrophically.As I have noted the second supply had only slightly domed caps wth no signs whatsoever of electrolyte leakage.
What I do not know is what happens to the smoothness of the DC supply voltage when the ESR rises.I have never had an oscilloscope conveniently attached to the supply output at the time of failure.(wry smile)
I hope you don't think that I am nit-picking but I really would like to be able to have a complete answer to this whole issue now out of sheer b...y mindedness.

I have explored the site you referred to but that is not to say that I recall it all.
I'll go back and have another look.

Regards and thanks to you both.

AL Ursich
08-08-2010, 8:05 PM

I made a ton of overtime money replacing bad caps when working at a Sony Service Center about 9 years ago....

So I always look at the Caps first.

Good Luck,


Dan Hintz
08-08-2010, 8:36 PM
I rather favoured the increase with cooling as this might explain why my supplies, which were in a quite cold(our winter) workshop, failed at switch-on so catastrophically.
At switch-on, the caps see a surge in energy... they are empty and look like near-shorts due to their low ESR. You will see a higher failure rate at turn-on, regardless of temperature, similar to the way an incandescent bulb will blow 95% of the time when you first turn it on... the filament is cold, offers a much lower resistance to the incoming current surge, and thermal shock weakens it.

Graham Symns
08-31-2010, 5:17 AM
Update on power supply repair.
It turns out finally for me that the ESR situatin was a non starter as I tested the filter capacitors with the ESR meter and it revealed that there was no problem in this regard as the source of the problem.
I finally got round to replacing the signal transistor,the FET and the resistor in the 2nd supply as replaced in the first supply.
While stripping the supply I noticed a melted portion of the insulating layer between the underside of the AC-DC convertor circuit board and the aluminium case.
Tracing the source of heat revealed that a diode had overheated for some reason and reached a temperature sufficient to melt a soldered joint and this allowed the device to protrude into contact with the insulating material.The offending device was hidden from view
The attached pic shows that to get at the device I had to remove a high value capacitor.
This revealed that the failed device was a rectifying diode IN5402.
It had ruptured along its length.
I replaced this with the nearest ,better, rated device IN5406 (1000v 3A)
After reassembling the power supply and installing it in the chassis and the application of power I was rewarded with 2 green LEDs and 48V on the meter.
I hope that this provides some help for anyone else who has a similar problem with a power supply and who needs a bit of encouragement will take something from this exercise.
I am having a bit of bother attaching the pix so I will close for the moment
and send another post with them

Graham Symns
08-31-2010, 5:40 AM
Further to my previous post here is the pix.
There is a diode to the right side of the pwb and its mate is to the left in the area of the exposed copper where the solder mask has been removed to allow for soldering of the replacement device.
The diode to the right was also replaced as it could have been compromised by the failure of the left hand unit.
To the right of the circuit board can just be seen the failed device.



andrew zen
08-31-2010, 3:46 PM

You have balls of steel for investigating this and doing the work yourself. Of course I am referring to your IKO bearings and their patented "C-lube" rolling guide series using Japanese steel for the bearings.

Please keep us updated as you turn this power supplies on. Maybe wear rubber shoes.

Graham Symns
08-31-2010, 4:36 PM
Hi Andrew,
I sure do not have balls of steel anywhere in a personal sense but I sure did have my fingers crossed at switch on,I can tell you!
Having recently retired I am time rich but still have a few things on the go.
A non engraver exercise is building a mobile unit to carry my De Walt thicknesser/planer and for it to double as a worktable/tablesaw extension.
Anyway thanks for your comments..much appreciated.


Roy Nicholson
09-02-2010, 4:15 AM
Give Frank a shout he'll tell you about it.


Roy N.