My DC freezer inverter has a failed component MUR2540CA, I don't know the function of this or an alternative or substitute for it. I could not find it locally.
The problem with the freezer is that it won't come on when power through 12v battery but comes on when powered via 220v ac.

Any help or guidance will be appreciated

 

hi Jzee.
Welcome to AAC.
You have not given your location, so we cannot suggest a local source.
Look at this link.
https://www.yoycart.com/Product/541328584757/

E

 

It's a Dual Shottky diode in a T0220 package.




Try also a Mbr3010ntu

https://www.mouser.co.uk/ProductDet...child/MBRP3010NTU?qs=sDn3NgULpDPczjmjJVpwsg==

 

I know I can buy it on line but will take a while before it arrives my country Nigeria. I need to put the freezer to use cos that the only one I have cos I live off grid. My thought is to understand through othersbwhat exactly that piece would be doing in the circuit and to know if there is an equivalent or substitute

 

RE: ""I could not find it locally""
Then why to not find it internationally??
For exapmple in these 4 stores below
https://octopart.com/search?q=MUR2540&start=0

 

RE: ""I could not find it locally""
Then why to not find it internationally??
For exapmple in these 4 stores below
https://octopart.com/search?q=MUR2540&start=0

Yea, I know, am just wondering if anyone out there has idea what exactly it is and if it has a substitute

 

Yea, I know, am just wondering if anyone out there has idea what exactly it is and if it has a substitute

READ POST #3!

 

Am still learning. May be you would like to explain further. I tried the link but saw list of countries. Yes, I can see you said it is Shockley diodes....

READ POST #3!

 

Hello,

Can you post a picture of the diode?
There are several types that are called MUR2540.
The ones shown by the others are dual diodes in a TO220 housing, but there are also studded single diodes with the same number:
http://www.datasheet4u.com/datasheet-pdf/MCC/MUR2540/pdf.php?id=1125776

Bertus

 

I know I can buy it on line but will take a while before it arrives my country Nigeria. I need to put the freezer to use cos that the only one I have cos I live off grid. My thought is to understand through othersbwhat exactly that piece would be doing in the circuit and to know if there is an equivalent or substitute

Shottky barrier rectifiers are very fast and can't be replaced with regular silicon types. A replacement needs both higher voltage and current rating - consider a bigger package style if there's room on the heat sink.

 

It is extremely unlikely that it is a schottky rectifier. The part number fits with a line of fast recovery PN junction rectifiers from Motorola from years gone by. (Mota used MBR for schottky and MUR for ultrafast conventional). I can't find that particular part number in any of my old Motorola data. Some other companies used the same numbering convention and offered parts never made my Motorola (now ON Semiconductor). I'll check some older General Instrument and General Semiconductor data to see if I can find it.

A photo of the device will be helpful. There are likely several suitable substitutes if it is plastic packaged (unlikely with the CA suffix; CT was/is a common suffix for TO-220).

 

Hello,

I looked in the 1988 motorola databook and found the MUR25XX to be a studded diode:



Please post a photo of the diode to be sure.

Bertus

 

It is extremely unlikely that it is a schottky rectifier. The part number fits with a line of fast recovery PN junction rectifiers from Motorola from years gone by. (Mota used MBR for schottky and MUR for ultrafast conventional). I can't find that particular part number in any of my old Motorola data. Some other companies used the same numbering convention and offered parts never made my Motorola (now ON Semiconductor). I'll check some older General Instrument and General Semiconductor data to see if I can find it.

A photo of the device will be helpful. There are likely several suitable substitutes if it is plastic packaged (unlikely with the CA suffix; CT was/is a common suffix for TO-220).

There's probably a data manual on archive.org. identify the ratings and there's probably a better modern replacement.

 

Hello,

@ian field , I looked in the motorola folder of this page:
https://the-eye.eu/public/Books/bitsavers.org/bitsavers.informatik.uni-stuttgart.de/components/
As you can see there are MANY manufacturers given on the page.

Bertus

 

I looked through several old selector guides and data books from various manufacturers and I can't find that part number. I would expect an MUR2540 to be a 25 A 400 V part, but I can't find any hint that Motorola ever made ultrafast of that current rating at 400 V. An MBR2540 would be a 25 A 40 V schottky, many of which were/are dual common cathode types. I haven't checked International Rectifier data, but IR was never big on second-sourcing other mfr's.

There will be something that will replace it, though stud mount devices are far less common than they used to be.

 

Hello,

@ebp , You are right about the max voltage on the motorola parts.
The page I posted only goes upto 200 Volts.
In post #9 I posted a datasheet from MCC, that goes upto 600 Volts.

Bertus

 

I am only assuming since you don't give mutch information that since its a 12V freezer. That it uses a compressor controller similar to this. The 2 top components are Shotkey Diodes a part of the inverter circuit to give about 30V dc to drive the compressor circuit.

 

Or it could be one of these same principal, but has a 240V ac powersupply built in.

 

I looked through several old selector guides and data books from various manufacturers and I can't find that part number. I would expect an MUR2540 to be a 25 A 400 V part, but I can't find any hint that Motorola ever made ultrafast of that current rating at 400 V. An MBR2540 would be a 25 A 40 V schottky, many of which were/are dual common cathode types. I haven't checked International Rectifier data, but IR was never big on second-sourcing other mfr's.

There will be something that will replace it, though stud mount devices are far less common than they used to be.

Its essentially a Motorola number - but there should be at least a couple of "second sources" because the military won't buy unless there is.

Sometimes you have to trim the prefix and search for the base number - but you might have to explain to google what it is.

 

"Sometimes you have to trim the prefix ..."

I've done all of that, but I think that is what got us to the notion of it being an SBR.
I can find no evidence that the MUR series was ever popular and most of the parts Mota produced disappeared quite quickly. I've used some of the low-current axial types. The FEPxxxx series from Vishay (originally General Instrument) would be suitable if the original is in a plastic package. I have a couple hundred in assorted voltages in TO-247 kicking around.

The C in the part number suggests "commercial" specs, so the military wouldn't use them in any case. I suspect General Semi and IR had most of the military market cornered. Mota did have mil qualified diodes but almost all were JEDEC registered numbers.

bertus's post at #9 seems the most plausible at this time. We really need the TS to post a pic or at least describe the part.