Repair of the switching power supply PRN150M-6 (EM9005 PS / AC) / SurprizingFacts

Power supply PRT EM9005 PS / AC (PRN150M-6) from MRV, 150 W, 12V, 12.5A, AC Input 100-240Vac.

The power supplies EM9005 PC / AC are part of the network industrial optical switches MRV OptiSwitch 9xxx series in the amount, as a rule, Two pieces. There are no questions to the network equipment, which can not be said about power supplies, which often fail. In most cases, private repair organizations are not responsible for repairing these switching power supplies (UPS) because of the lack of repair circuits and high density of radioelement placement. In addition, the cost of one power supply unit from official representatives exceeds 50 thousand rubles per unit (53 thousand Aug. 2016).

The gap in the absence of a repair scheme was solved by reverse engineering, a "donor" power unit , A soldering iron and a flashlight. Who is interested in the scheme of this power supply unit and its description, please:

One block was decoupled so that you could examine all the tracks of the circuit board and get to the hidden radio elements. The printed circuit board, as it turned out, is beautifully illuminated using a conventional flashlight. Thus, the scheme, gradually, was copied onto paper, and then in Visio. The scheme is of a repair nature and does not pretend to an assembly plant layout, because the values ​​of all elements (especially SMD capacitors) were not considered. But, if denominations are very necessary, they can be "pulled out" from official datasheets to the main components of the scheme. For example, the circuitry of the KKM kerchief of the power supply unit, almost completely corresponds to the description of its controller UC3854N.

The MRV switch, which includes these power supplies.

Our Switches MRV OS9048FX-4G

Other Viewpoints of the Power Supply:

Power Supply Tag PRN150M -5 (EM9005 PS / AC)

The top view of the power supply unit PRN150M-6 (EM9005 PS / AC)

Rear view of power supply unit PRN150M-6 (EM9005 PS / AC)

So, if you identified your "beast", do not simmer hook, description attaching the power supply circuit thereto, the description of the most characteristic bounce PSU check blank, the control check point. All the driving under the spoiler:

The circuit, the description of the power unit PRN150M-6 (EM9005 PS / AC)

I did not begin to spread all this "portyanka", 22 pages in volume about the boring description Block, its failures, etc. Put it all in a separate file " Description of operation of the UPS scheme PRN150M-6.doc " (File 12.6MB is uploaded to Scribd.com). By the way, Scribd strongly "cut" the graphic information in the document, so if you just need to look through, look – you can and in the web, if you need to work with the document – better swing. The experience of repairing this block is about 1.5 years. Through the hands passed, I think, more than 20 pieces of these power supplies. All the typical failures, successful / unsuccessful repair experience recorded in this file.

Description of operation of the UPS scheme PRN150M-6.doc (Scribd.com)

The electrical schematic diagram in the document is, but it sometimes needs to be more honorable , Sometimes it needs to be corrected, printed out on a large format, something to mark, so I upload a separate * .vsd file (Visio) with a schematic diagram of electrical principle on Google.docs.

Electrical schematic diagram in Visio:
The scheme of the BP PRN150M-6.vsd (Google.docs 1.2Mb).

For the "mass" repair of this power unit I recommend to make a "stand" for fixing the PCB, so that it would be safer and it would be possible to get to all radio elements. What is the "stand" of itself is:

Power supply testing and repair stand PRN150M-6 (EM9005 PS / AC)

Two rigid plates capable of removing heat. Plates of the same size, but with a different arrangement of holes for the fastening of cooling of radio elements. I found some sandwich panels for wall finishing. Panels made of aluminum with an interlayer of some kind of insulator, thickness, millimeters 5. In the area of ​​mounting the printed circuit board, the plate should be insulated. I just peeled off one layer of aluminum from the sandwich:

Power supply testing and repair stand. The board is isolated from the plates of the "stand."

In the right places on the plates small corners are fixed to fix the printed circuit board to the "stand". After assembling and screwing all the radio elements, the stand behaves rigidly, well removes heat, makes it possible to "pick" in the entire "stuffing" of the power unit. There is another option to make a stand for checking these blocks. Take one "donor". The body is cut with an engraving machine, or rather – cut the bottom, leaving all the fasteners in the right places. But – it's a pity. On the other hand, if you have 30 pieces of these blocks, and no one will fix them except you – a flag in your hands – boldly cut one body. For, like in any repair, there is at least one non-reusable power supply unit, in which the transformer burned and, frankly speaking, it's too lazy to bother.

Power supply. All the electrical circuits are available.

Another test requires a power cord with an incandescent lamp of E27 watts at 95 in the rupture (worst case), or a 220/220 V isolating transformer, also with a limiting safety lamp in the secondary winding (The best option, especially if you have RCDs). This is all described in the * .doc file. This is all necessary for your safety, and radio elements do not get in the case of "unsuccessful" repairs.

Special thanks to the guys from the forum cxem.net for help in explaining the principles of the CMC. This is the branch of the discussion of the refusal of the CMC in this power unit.

Thank you for your attention! I hope the article was useful.

P.S. The big request is not to write in a personal message like: "But, I have a power supply, and it has a fuse burned. So that it could be with him? "

  1. First: I know perfectly well what a Habr effect is
  2. Secondly: I'm not a Satan to repair all power supplies, I just sorted out the repair of this BP.
  3. Third: with the power supply unit can be anything you like! There are, of course, certain regularities, but they correspond to their BP type.