100 watt resistors needed for a one time job - did not expect them to look like this.

[62vauxhall]

I am at the tail end of a small project. I replaced two relays and all electrolytic capacitors (100uF and smaller) in a Sanyo 100 watt MOSFET amplifier. The service manual describes an adjustment proceedure that calls for a 100 watt 8 ohm resistor across + and - speaker terminals.

The resistors I've seen online that aren't hideously expensive look unfamilliar being encased in a heat sink. I guess I'm overly cautious but I don't want to spend $50 on two resistors for a five minute job and then find out I've bought the wrong type.

Would this style of resistor be suitable as a dummy speaker load?

 

[Vynuladikt]

How to Build a Big Dummy Load. (prosoundtraining.com)
heater elements for a few dollars at the hardware or big box and a bucket of water

 

[marcok]

https://www.amazon.com/LM-YN-Wirewo...id=1711654879&sprefix=8+ohm+lo,aps,165&sr=8-5
Better to secure on an alu bar.
Ciao
Marco

 

[62vauxhall]

How to Build a Big Dummy Load. (prosoundtraining.com)
heater elements for a few dollars at the hardware or big box and a bucket of water

That there's a big 'un.

 

[62vauxhall]

https://www.amazon.com/LM-YN-Wirewound-Electronic-Aluminium/dp/B076W5T9SL/ref=sr_1_5?crid=20RGZORW9Q0PD&dib=eyJ2IjoiMSJ9.zmacEBGBHhIpARag5NM4UjYvaOrM0SkEC9hSKCIlEKaOBrwWLIYLDek__kuhSw38339tP7EYv3AwY6RF4Wk3plQm1QYzhjITbWMxOWW-jtfFt0_MAn08tKbSSZEhz31RHByik_TN2bwxNIp3DDeOC_x2USEmygRCp075ccdIkJZ2VbDcqU5_f11OuRlbTJ1iBcQunz_oueY0fheSNtWOMWPsvXht6Z0SR03_4CYFnAE.LTRgIYoukFuF-zkWDhlFqSbw1usId2E8xxJTcDOiND4&dib_tag=se&keywords=8+ohm+dummy+load&qid=1711654879&sprefix=8+ohm+lo,aps,165&sr=8-5
Better to secure on an alu bar.
Ciao
Marco

I'll take that as an OK to use this resistor type.

There is a piece of aluminum here I can attach a resistor to and I will if gets overly warm. I don't think the proceedure I need it for will take very long. Just a matter of adjusting a couple of pots while monitoring voltage.

 

[laatsch55]

Just make it a non-inductive wirewound resistor
.

 

[Gepetto]

I'll take that as an OK to use this resistor type.

There is a piece of aluminum here I can attach a resistor to and I will if gets overly warm. I don't think the proceedure I need it for will take very long. Just a matter of adjusting a couple of pots while monitoring voltage.

Those resistors will not dissipate 100W without a heatsink

 

[wattsabundant]

Attached are photos of a 7.2 ohm load bank using water heaters. Here is a Home Depot link. 120 volt-2000 watt heater

Note that the elements must be submerged in a full bucket of water. At $10 each, It's reliable, as long as the bucket is full of water, and cheap. Without water, the plastic lid will melt in a few seconds.

 

[Gepetto]

Attached are photos of a 7.2 ohm load bank using water heaters. Here is a Home Depot link. 120 volt-2000 watt heater

Note that the elements must be submerged in a full bucket of water. At $10 each, It's reliable, as long as the bucket is full of water, and cheap. Without water, the plastic lid will melt in a few seconds.

Don't ask Don how he knows...

 

[wattsabundant]

A penalty must be inflicted as a result of stupidity. In this case the penalty was a minor burn on a couple fingers.

 

[mlucitt]

a minor burn on a couple fingers.

I believe many of us hold that honor...

 

[gene french]

ive been lucky so far....no finger burns...
just a loss of hair and reduced hearing in my left ear...

 

[62vauxhall]

Well, I've been proven wrong before and I appreciated the DIY suggestions but I'm going with those chassis mount 100 watt resistors.

If I forsaw myself needing large dummy speaker loads in the future, it might prompt me cobble one together. This is where I could be mistaken but I imagine those resistors should be OK for the length of time it I think it will take to adjust a couple of pots.

FWIW, I checked the local building supply store and did not see a 2000W water heater element. There are 3000W elements for $30 each and I'd need to scare up a bucket, a hole saw and whatever wire is needed. I've got none of that stuff handy so would likely need to buy it all.

A Sanyo Plus P55 is not an example of a super duper amplifier.

 

[Gepetto]

Well, I've been proven wrong before and I appreciated the DIY suggestions but I'm going with those chassis mount 100 watt resistors.

If I forsaw myself needing large dummy speaker loads in the future, it might prompt me cobble one together. This is where I could be mistaken but I imagine those resistors should be OK for the length of time it I think it will take to adjust a couple of pots.

FWIW, I checked the local building supply store and did not see a 2000W water heater element. There are 3000W elements for $30 each and I'd need to scare up a bucket, a hole saw and whatever wire is needed. I've got none of that stuff handy so would likely need to buy it all.

A Sanyo Plus P55 is not an example of a super duper amplifier.

View attachment 80803

Yup, that's a baby...