RW47g470 145w ceramic 47 ohm resistor whats NOM mean?

Passives Resistors
1

was made by IRC now TT electronics
part number RW47G470
res 47 ohms
145w NOM
5905-879-3369 on it which is
5905-00-879-3369
what does the NOM mean?
I was curious on any specs on it such as if non inductive.

2

Welcome to the forum.

I can’t find a part number of RW47G470 or any TT/IRC resistor with a similar part number. The other code numbers also do not show up in a search.

Can you provide a data sheet link or different part number?

3

I have search the web also… data sheet sites… I contact TT of coarse all the old info is gone from merger… The rep suggested I try Digikey…
the only other numbers are 214 6326
214 eia code
6326 date code 1963 26 week maybe

4

Can’t be sure without seeing the data sheet context.

However, NOM usually indicates nominal, meaning it could be higher or lower by some amount.

1 Like
5

Hello Dougmc,

Agree with @PaulHutch, the NOM designation most likely implies nominal or typical resistance. It’s likely related to the concept tolerance.

As a bit of trivia: This is a military resistor. The Federal Supply Class (FSC) of 5905 identifies resistors. Th National Stock Number (NSN) of 5905-00-879-3369 identifies a particular resistor.

Also, the fact that the -00- was added implies this is an old resistor manufactured at a time when the NSN formatting was in transition. My guess is that this part is 50 years old.

Best Wishes,

APDahlen

P.S. Please add a picture and we may be able to better judge if this is non inductive. Contextual and application glues are important.

P.P.S. You may be interested in this piece where I explore the nature of wire wound resistors: Discover the Unexpected Frequency Response of Wire Wound Resistors - Education - Electronic Component and Engineering Solution Forum - TechForum │ DigiKey. The featured equipment provides a quick impedance measurement.

1 Like
6

I added the 00 seems to help with other part numbers search. Just means usa

20240426_124010
20240426_1240101920×1920 135 KB

20240426_124015
20240426_1240151920×1605 92.7 KB

20240426_123938
20240426_1239381920×869 141 KB

7

Hello Dougmc,

With near certainty we can say this is a wire wound device. Very similar to the one on the I mentioned in the previous forum port.

We can see the individual wraps of wire.

Sincerely,

Aaron

Ref: Discover the Unexpected Frequency Response of Wire Wound Resistors - Education - Electronic Component and Engineering Solution Forum - TechForum │ DigiKey

8

Thanks I read thru that,
also appreciate assistance

1 Like
9

Let us know if we can assist in the future.

Out of curiosity, what is your application for the power resistor? Is it audio of are you looking to make an RF dummy load?

Have a good weekend.

r/

APD

P.S. Have you seen the Heathkit HN-31 Cantenna. I believe this product used a carborundum resistor. There were ceramic based products - essentially hollow tube with resistive material baked into the ceramic. The benefit was a non-inductive power resistor.