help, need diode

This is the place for any magazine-related discussions that don't fit in any of the column discussion boards below.
User avatar
frhrwa
Posts: 897
Joined: Mon Feb 04, 2002 1:01 am
Location: Eastern Washington (state) and N. Las Vegas (winter)
Contact:

help, need diode

Post by frhrwa »

I need a couple diodes that go on the armature of a power generator... its a porter cable 5500 watt unit.. the diodes blew out, they are 10amp 1000v peak units (legacy style) any help appreciated... where to buy etc.. the Spokane Washington area doesn't seem to have an electronics store worth a hoot... thanks, wayne email me at [email protected]

the diode says LT90 10A07 on it... I think it may cross to VTE5817HC ?
User avatar
haklesup
Posts: 3136
Joined: Thu Aug 01, 2002 1:01 am
Location: San Jose CA
Contact:

Post by haklesup »

A quick search on those numbers didn't lead anywhere especially without knowing the manufacturer. but if you change V to an N (NTE5817HC) you get http://www.nteinc.com/specs/5800to5899/ ... c_17hc.pdf

If the P/N turns out to be a dead end, simply look for a 1000V, 10A or greater diode in the same package.

Here are a few links to get you started:
http://www.irf.com/package/pkdfast.html

http://www.irf.com/product-info/diodes/
Try searching under "High powered fast recovery discretes"

Usually its no problem (as in the recitifier application) to substitute a diode with a higher voltage or current so long as it is in the same package so it will fit. Usually don't want to sub a Si for a Schottkey but the other way around is sometimes Okay but best to avoid it.
User avatar
dacflyer
Posts: 4748
Joined: Fri Feb 08, 2002 1:01 am
Location: USA / North Carolina / Fayetteville
Contact:

Post by dacflyer »

i have worked ona simmelar generator,,the dioad seems overkill to me,
but theone i had was the same as you describe,, its mounted on the fan of the armature. stud mount..

just for kicks i replaced it with a 5 amp 400 volt stud mount dioad i had in my junk box.. i tried it and it worked just fine.. i expected it to fail after a heavy load, but it didn't and it has lasted 4 years now...

i did have to flash the field after i got it running.. so far so good..
i do not know what could have blown the dioad in the 1st place.. it was a mystery to me also..

the armature is self exciting, its got some magnetic residue..once its spinning its supposed to excite and create a full magnetic charge , i guess the dioad keeps the polarity on the armature form switching polarity..

good luck,,
User avatar
Janitor Tzap
Posts: 1707
Joined: Sat Aug 12, 2006 5:17 pm
Contact:

Re: help, need diode

Post by Janitor Tzap »

frhrwa wrote:I need a couple diodes that go on the armature of a power generator... its a porter cable 5500 watt unit.. the diodes blew out, they are 10amp 1000v peak units (legacy style) any help appreciated... where to buy etc.. the Spokane Washington area doesn't seem to have an electronics store worth a hoot... thanks, wayne email me at [email protected]

the diode says LT90 10A07 on it... I think it may cross to VTE5817HC ?
I broke out my ECG Guide and came up with nothing.

You should try going to Porter Cable with the model number of the generator,
and see if they carry replacement parts for your model.

Thou, before you repair your generator.
I would find out what caused the diodes to blow in the first place.

Signed: Janitor Tzap
User avatar
jollyrgr
Posts: 1289
Joined: Thu Jan 03, 2002 1:01 am
Location: Northern Illinois
Contact:

Post by jollyrgr »

These are hard to find but not impossible. Go here:

http://www.surplussales.com/semiconduct ... des-1.html

There is a six amp 1KV diode. Worse case you parallel two of these. Not the most advisable way of doing things but it would work.

Here is the same type of diode only a better price of two for a dollar.

http://www.allelectronics.com/cgi-bin/i ... IODE_.html


Then there are the small engine shops that sell direct replacments. Here are some Coleman parts:

http://www.jackssmallengines.com/gencol.cfm

You might also try motor/generator rebuild shops as many elevator motors are DC. I've also seen high current DC used in old lighting systems.
No trees were harmed in the creation of this message. But billions of electrons, photons, and electromagnetic waves were terribly inconvenienced!
User avatar
jollyrgr
Posts: 1289
Joined: Thu Jan 03, 2002 1:01 am
Location: Northern Illinois
Contact:

Post by jollyrgr »

dacflyer wrote: {SNIP}
i did have to flash the field after i got it running.. so far so good..
i do not know what could have blown the dioad in the 1st place.. it was a mystery to me also..
{SNIP}
DacFlyer,

I knew you had to flash the field winding in DC generators for old cars and airplanes. I've never done it, just know it needs to be done. Those use a battery and there is a polarity associated. How do you, and why do you, need to do this on an AC generator? Where is the "battery"? Is this a "sneak" voltage off the magneto or is the a permanent magnet (psuedo from residue in the windings) that needs to be compensated for?
No trees were harmed in the creation of this message. But billions of electrons, photons, and electromagnetic waves were terribly inconvenienced!
User avatar
Chris Smith
Posts: 4325
Joined: Tue Dec 04, 2001 1:01 am
Location: Bieber Ca.

Post by Chris Smith »

Try "All Electronics". they usually stock diodes cheaply and even carry bridge rectifiers [4 diodes in a package] in "hocky pucks" that can carry these kinds of loads.

Their basic loads usually cover what you need also.

Also consider adding some MOVs to take some of the brunt, before the diode has to carry the full load.


www.allelectronics.com/


.2 AMP, 6000 V RECTIFIER
CAT# R6000

3AMP/1000 PIV
CAT# 1N5408

6 AMP 1000 VOLT DIODE
CAT# P600M

40 AMP 1200 VOLT FULL WAVE BRIDGE, WIRE LEADS
CAT# FWB-412

8 AMP, 1000 V BRIDGE RECTIFIER
CAT# FWB-80


You can also double or quadruple [parallel and series units] diodes for a higher voltage and amperage rating.
User avatar
dacflyer
Posts: 4748
Joined: Fri Feb 08, 2002 1:01 am
Location: USA / North Carolina / Fayetteville
Contact:

Post by dacflyer »

its gonna be hard to add anything more to that armature,,because its gonna be spinning at 3,600 rpms

the dioad i think is mounted on the cooling fan blade.( stud mount)

it he did add a MOV..he'd have to be careful, of it not slinging off, and or upsetting the balance.
User avatar
Chris Smith
Posts: 4325
Joined: Tue Dec 04, 2001 1:01 am
Location: Bieber Ca.

Post by Chris Smith »

Any MOV should be over rated at the high end, [+10% over norm] simply to catch transients or extra high voltage spikes, not to load anything down under normal conditions.
User avatar
dacflyer
Posts: 4748
Joined: Fri Feb 08, 2002 1:01 am
Location: USA / North Carolina / Fayetteville
Contact:

Post by dacflyer »

strange, frhrwa hasn't been back here yet to check any of his replys....
User avatar
frhrwa
Posts: 897
Joined: Mon Feb 04, 2002 1:01 am
Location: Eastern Washington (state) and N. Las Vegas (winter)
Contact:

Re: help, need diode

Post by frhrwa »

Janitor Tzap wrote:
frhrwa wrote:I need a couple diodes that go on the armature of a power generator... its a porter cable 5500 watt unit.. the diodes blew out, they are 10amp 1000v peak units (legacy style) any help appreciated... where to buy etc.. the Spokane Washington area doesn't seem to have an electronics store worth a hoot... thanks, wayne email me at [email protected]

the diode says LT90 10A07 on it... I think it may cross to VTE5817HC ?
I broke out my ECG Guide and came up with nothing.

You should try going to Porter Cable with the model number of the generator,
and see if they carry replacement parts for your model.

Thou, before you repair your generator.
I would find out what caused the diodes to blow in the first place.

Signed: Janitor Tzap
I did go to porter cable, they will only sell me a complete armature.. won't sell the diodes by themselves..
User avatar
Janitor Tzap
Posts: 1707
Joined: Sat Aug 12, 2006 5:17 pm
Contact:

Re: help, need diode

Post by Janitor Tzap »

frhrwa wrote:
Janitor Tzap wrote:
frhrwa wrote:I need a couple diodes that go on the armature of a power generator... its a porter cable 5500 watt unit.. the diodes blew out, they are 10amp 1000v peak units (legacy style) any help appreciated... where to buy etc.. the Spokane Washington area doesn't seem to have an electronics store worth a hoot... thanks, wayne email me at [email protected]

the diode says LT90 10A07 on it... I think it may cross to VTE5817HC ?
I broke out my ECG Guide and came up with nothing.

You should try going to Porter Cable with the model number of the generator,
and see if they carry replacement parts for your model.

Thou, before you repair your generator.
I would find out what caused the diodes to blow in the first place.

Signed: Janitor Tzap
I did go to porter cable, they will only sell me a complete armature.. won't sell the diodes by themselves..
Well that stinks.

Next option would be to goto a small motor; generator rebuilder.
They probably would have the diodes that fit that armature.
If your lucky they may do a core swap of your old armature for a rebuilt one.

I'm lucky in that I have a rebuilder close by.
Thus, when the brushes for my alternator wore out,
He had the parts for it.

Good luck frhrwa.

Signed: Janitor Tzap
rshayes
Posts: 1286
Joined: Tue Mar 04, 2003 1:01 am
Contact:

Post by rshayes »

I would look for a diode by its characteristics rather than depending on cross references.

First, look at the diode package. The new part should be the in the same package. If it is a stud mounted diode, a few measurements should identify the diode package.

Then go to manufacturer's web sites or possibly the Mouser or Digikey catalogs and try to find a diode with the same ratings in the same package. Since this is 60 Hz, you shouldn't need special characteristics such as fast recovery, etc.

Trying to get cross references between unknown manufacturers' house numbers will be a very frustrating experience.

Transient supressors on the output windings of the generator may give some protection without unbalancing the armature.
User avatar
Chris Smith
Posts: 4325
Joined: Tue Dec 04, 2001 1:01 am
Location: Bieber Ca.

Post by Chris Smith »

Sorry, there is no rocket science involved.

Buy them, install them, and over rate the MOVs like every one else.
User avatar
Edd
Posts: 885
Joined: Sun Jan 27, 2002 1:01 am
Location: Dallas Tx
Contact:

Post by Edd »

Ohhhhh….KJR Land Inhabitant:

I was initially thrown by your casing / housing reference to :

Legacy…………………..Style
A kind name for the historical or "old way" to do something in computers.

Since I was expecting the unit to be in a common larger R6 casing in order to be used in a confined mounting as well …….. so:

This is probably your exact diode a 1000Vpiv @ 10 Amp and its configuration, isn't it ?

http://www.ortodoxism.ro/datasheets/diodes/ds28010.pdf

Image


Your further tie in to Digi Key for info:
http://rocky.digikey.com/scripts/Produc ... &M=10A05-T

Their specific data sheet again:
http://www.diodes.com/datasheets/ds28010.pdf

73's de Edd
[email protected] ...........(Interstellar~~~~Warp~~~Speed)
[email protected].........(Firewalled*Spam*Cookies*Crumbs)
:grin: :razz: :grin:

When I go shopping, I love to freak out salespeople. They ask me if they can help me, and I say,
"Have you got anything I'd like?" Then they ask me what size I need, and I say, "Extra medium."

Image

.
Post Reply

Who is online

Users browsing this forum: No registered users and 28 guests