Anybody Know What This Is?

That Man

Member
That's right. That tiny little thing is a rectifier. I've never seen one in the field before, apparently. I guess I thought they would be bigger, and have some sort of label. This forum's great.
 

GeorgeB

ElectroHydraulics engineer (retired)
Location
Greenville SC
Occupation
Retired
I'm with the bridge rectifier crowd. They come smaller and larger. I'm used to symbols for AC in and DC out, not a D on the heat sink extension.
 

Jraef

Moderator
Staff member
Location
San Francisco Bay Area, CA, USA
Occupation
Electrical Engineer
Yep, diode bridge rectifier.

The one terminal that is at 90 deg. to all the others is always the + DC terminal, the - DC terminal is always kitty-corner to it, then the other two corners are the AC terminals.That way you can't mess up and put AC in the DC side or vice-versa (if you know that...).
 

Hv&Lv

Senior Member
Location
-
Occupation
Engineer/Technician
Cast my vote.
Rectifier.
That isn’t what the “D” is for though. That is the labeling for the schematics.
we have lots of them in 115kV breakers.
AC in, DC out, as stated.
Had one CCVT at a station that was a little low on output. Kept blowing out rectifiers.
Ended up putting a small 500VA series XF in to boost the voltage up to about 130V..
 

LarryFine

Master Electrician Electric Contractor Richmond VA
I've been into electronics since I was a kid (physically, I mean). I recognized the full-wave bridge rectifier immediately, probably with a 25-amp rating.
 

steve66

Senior Member
Some type of rectifier was my first thought too. I guess you just have to have seen them before. Not sure if anyone could know if it is half wave or full wave just by looking at it, though.

Another clue includes 4 wires/terminals (Although I'm not sure who made them all black - bad planning on the part of whoever assembled this panel, IMO.)

Also, its usually obvious there is both AC and DC in the panel . For example, AC input from a 120V panel, and relays with DC coils). I would normally expect to also see a step down transformer, and either a power supply or at least some filter caps.
 

Besoeker3

Senior Member
Location
UK
I've been into electronics since I was a kid (physically, I mean). I recognized the full-wave bridge rectifier immediately, probably with a 25-amp rating.
Yes, looks to be about that size but I doubt that you'd get rating that unless it is mounted on a heatsink rather than the back panel. The ones we used were IR, usually 26MB120. Shows the chamfer corner.

 
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Besoeker3

Senior Member
Location
UK
Another clue includes 4 wires/terminals (Although I'm not sure who made them all black - bad planning on the part of whoever assembled this panel, IMO.)
The wires do have identification ferrules. That's how we did small wiring in our control panels. Black 1.0mm^2 with wires numbered as per the schematic.
 
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