Fusible Resistors

[Thomas Arundel]

We got a call from a customer the other day who asked if we would put
together some Fusible resistor sets for (TV) repair shops.

We're a component supplier that specialises in selling sets of components
e.g. resistors, capacitors, SMDS etc, the idea being that it a much easier
way to stock the bench-top. From what he was saying, a kit of fusible
resistors might go down quite well, especially because apparently minimum
order quantities make these components expensive (at least in the UK)

I wondered if you guys might have any thoughts about which values / wattages
/ packages are most commonly required when repairing equipment, and what
characteristics (if any) we should pay special attention to. I noticed that
some suppliers offer these upto 10k - surely they're most useful in lower
voltages. Do values adhere to any particular E-series?

We were proposing to put together a set to sell for around £10 / $18 with as
wide a range of values as possible...

Thanks, Tom.

 

[Thomas Arundel]

some suppliers offer these upto 10k - surely they're most useful in lower

voltages.

Sorry - meant resistances!

Tom.

 

[Ron(UK)]

Sorry - meant resistances!

Tom.

Altho a fusible resistor kit is a good idea, don't many manufacturers
insist that ion the case of safelty components, the replacement part is
the exact part number obtained from them in order to comply with safety
regulations

Ron

 

[Thomas Arundel]

Altho a fusible resistor kit is a good idea, don't many manufacturers

insist that ion the case of safelty components, the replacement part is
the exact part number obtained from them in order to comply with safety
regulations

Yes, that might well be the case - though I wonder in practice how many of
these parts are actually available from the original manufacturer - my
understanding from our local repair shop was that most manufacturers were
only interested in selling a complete replacement board. The shop isn't too
keen on this, because it takes away their margins, and the boards are so
expensive that most customers choose to buy a new product (which is exactly
what the manufacturers want).

Interesting question though - if you (as a shop) repair something, don't you
invalidate its warranty? That being the case, does a repair shop have to
issue its own warranty?

Also whose safety regulations are you referring to?

Tom.

 

[kip]

Oh! Boy

 

[Thomas Arundel]

Oh! Boy

Come on - throw me a bone here! ;-)

 

[Ron(UK)]

Generally a warranty repair is carried out by a service dept who are
nominated to perform such repairs. If an item is out of the
manufacturers cover, then the repair should be guaranteed for a set
period, generally 90 days here in the uk.

As for the regulations, off the top of my head I`m not sure of the
relevant regulation number, but many service sheets carry a symbol next
to components like transformers, fuses and fusible resistors etc.
Basically it means that this is a safety component and must be replaced
with the manufacturers exact replacement part. It also means that
instead of paying something like 18 little pennies for the part, you end
up paying £2.50 or more!

Ron

 

[N Cook]

We got a call from a customer the other day who asked if we would put
together some Fusible resistor sets for (TV) repair shops.

We're a component supplier that specialises in selling sets of components
e.g. resistors, capacitors, SMDS etc, the idea being that it a much easier
way to stock the bench-top. From what he was saying, a kit of fusible
resistors might go down quite well, especially because apparently minimum
order quantities make these components expensive (at least in the UK)

I wondered if you guys might have any thoughts about which values / wattages
/ packages are most commonly required when repairing equipment, and what
characteristics (if any) we should pay special attention to. I noticed that
some suppliers offer these upto 10k - surely they're most useful in lower
voltages. Do values adhere to any particular E-series?

We were proposing to put together a set to sell for around £10 / $18 with as
wide a range of values as possible...

Thanks, Tom.

--
Thomas Arundel
TL: +44 (0) 870 750 4468
FX: +44 (0) 870 137 6005
EM: [email protected]

That would be easier than re-using fusible resistors, or at least
silk screen marked safety resistors, from soon to be scrapped boards.

 

[Thomas Arundel]

That would be easier than re-using fusible resistors, or at least

silk screen marked safety resistors, from soon to be scrapped boards.

for sure it would... Any hints on what sort of resistances / wattages are
most commonly required?

 

[Ron(UK)]

for sure it would... Any hints on what sort of resistances / wattages are
most commonly required?

A quick scan through my resistor folder[1] shows R22, 1R, 2R2, 4R7,10R,
& 47R in .25 watt 2R2 in 1 watt and 15R in 2 watt (probably for some
once common psu) and some yellow sleeving covered R22 marked Phillips vcr...

[1] photographic 35mm slide album with the resistors in little poly
bags that just fit in the slide pockets perectly.


Ron

 

[N Cook]

for sure it would... Any hints on what sort of resistances / wattages are
most commonly required?

I would suggest 0.5W in resistor values
1,2/2.2 , 4.7 , 10
20,47,100
200,470

Smaller than 1 ohm tend to be higher wattage 'emitter' resistors
I don't remember coming across more than 470 ohm fusible
resistors in any of the mainly domestic kit I repair.

 

[Thomas Arundel]

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I would suggest 0.5W in resistor values
1,2/2.2 , 4.7 , 10
20,47,100
200,470

Great Thanks guys, we'll get sourcing