Sold/Expired SOLD OUT: JM-SST: PWM soft-starter Batch 2

[JimmyM]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

I just hooked up a JM-SST to my LarryK14 and it works perfectly.

Good job JimmyM and thank you for your time and expertise.

It is nice to be able to use the stock switch again. (I had a 50 amp toggle switch under the handle before.) I am running 4000 mAh LiPos 8S2P. The pack stays at 30.7V under the 20A load for a little over 600W. (According to my Super Whatt Meter.) I previously flashed a Q4559X on 8S2P and then ran 7S2P to avoid flashing another. I did not measure Vbulb. It's nice to be able to overdrive this without worry.

I really hope that a higher voltage version becomes available for my HyperBlitz. (Hint, Hint.)

Regards,
Mark

OK. Got the hint. It's been taking a while to get to the "higher power" designs because of projects in the queue. But since this design seems to be robust enough. I've got a proposal for you. I've got a few extra JM-SSTs held in reserve. I'll swap out the MOSFET for a 60V one I have. I've still got your address. I'll send it to you, and you test it. If it works, then you pay. If it blows up, just send it back.
Sound like a good idea?

 

[JetskiMark]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

OK. Got the hint. It's been taking a while to get to the "higher power" designs because of projects in the queue. But since this design seems to be robust enough. I've got a proposal for you. I've got a few extra JM-SSTs held in reserve. I'll swap out the MOSFET for a 60V one I have. I've still got your address. I'll send it to you, and you test it. If it works, then you pay. If it blows up, just send it back.
Sound like a good idea?

That sounds like an excellent idea. Thank you. I am sure that it will work well, since the wattage will be less than what the Q4559X draws. Would it be possible to have leads for an external pot while keeping the on-board one?

Regards,
Mark

 

[JimmyM]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

That sounds like an excellent idea. Thank you. I am sure that it will work well, since the wattage will be less than what the Q4559X draws. Would it be possible to have leads for an external pot while keeping the on-board one?

Regards,
Mark

Yeah. I can do that. I'll have to swap one of the resistors and do a little mod to a copper trace. You'll need a 500K external pot. I'll see if I have some flexible small gauge wire lying around for connection to the external pot.

 

[petrev]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

Hi Jim

#B2-15 JM-SST

PP sent

Hold and post with other parts of care package - let me know extra costs etc. . .

Thanks - Keep up the Good Work
Pete

 

[JimmyM]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

Will do.

 

[plasmaman]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

Hey Jimmy!
Pete and I have a plan...but it means putting 30A through the board using a 1000w 28v par64 lamp on a 36v pack...are you up for it on FAR (fail and return)!
PP on the way for #16!
John

 

[cat]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

wow! A real turbo head! 36V...10D. Some extension you'll need.
But you've found me a good reflector / a good lamp to make a spotlight with. Better and cheaper than a Lightforce plastic one. :naughty:

 

[JimmyM]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

Plasmaman, you and Pete are NUTS!
1000W? Without heatsinking it will overheat and desolder itself from the board, possibly causing a short.
You have to do test runs outside the light first. The only risk to the JM-SST is burning up the MOSFET.
I'd really prefer it if you did an external mount of dual MOSFETs. It's not the MOSFET itself that's the problem. It's the ability to shed heat.
What is the fully charged pack voltage?

 

[JetskiMark]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

Hello JimmyM

I received my JM-SST-HV-ET today, thank you. I need to get a suitable pot before I can install it. I want to add a secondary "safety" switch. I would like to find a pot with a switch built in. Something like this might fit. I only have about 9/16" of depth where I would like to mount it. So I could not fit something like this.

If I used a pot that was less then 500K, (like the 10K in the first link) would that cause the brightness to only be able to be turned down slightly? I was hoping to be able to get a pot locally, but I will probably have to order one.

I will figure all of this out when I get back from the SHOT Show.

Regards,
Mark

 

[plasmaman]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

Plasmaman, you and Pete are NUTS!
1000W? Without heatsinking it will overheat and desolder itself from the board, possibly causing a short.
You have to do test runs outside the light first. The only risk to the JM-SST is burning up the MOSFET.
I'd really prefer it if you did an external mount of dual MOSFETs. It's not the MOSFET itself that's the problem. It's the ability to shed heat.
What is the fully charged pack voltage?

:twothumbsMmmmm, you're not wrong!
I charged the pack a few hours ago, and it now shows 34.5v (10 x A123)
I did attach a finned heatsink to the top of the FET as part of the original build, so I guess I should check temps with the 600w lamp fired up...... I'll let you know.

 

[petrev]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

:welcome: . :twothumbs . . . :candle: . :thinking:

Any suggestions on the 2x MOSFETs ? I still have a couple of 2804s ?

But there is lots of room in the host so any really big ones that would work would be good ! ! !

Cheers Pete

 

[petrev]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

Hello JimmyM

I received my JM-SST-HV-ET today, thank you. I need to get a suitable pot before I can install it. I want to add a secondary "safety" switch. I would like to find a pot with a switch built in. Something like this might fit. I only have about 9/16" of depth where I would like to mount it. So I could not fit something like this.

If I used a pot that was less then 500K, (like the 10K in the first link) would that cause the brightness to only be able to be turned down slightly? I was hoping to be able to get a pot locally, but I will probably have to order one.

I will figure all of this out when I get back from the SHOT Show.

Regards,
Mark

Hi

This is 17mm deep ? ? ? With a Push Switch - may still be too deep !

Pete

 

[JimmyM]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

Hello JimmyM

I received my JM-SST-HV-ET today, thank you. I need to get a suitable pot before I can install it. I want to add a secondary "safety" switch. I would like to find a pot with a switch built in. Something like this might fit. I only have about 9/16" of depth where I would like to mount it. So I could not fit something like this.

If I used a pot that was less then 500K, (like the 10K in the first link) would that cause the brightness to only be able to be turned down slightly? I was hoping to be able to get a pot locally, but I will probably have to order one.

I will figure all of this out when I get back from the SHOT Show.

Regards,
Mark

10K would give you a 1% variation in duty cycle. Not much use. This part from digikey CT2232-ND would work. It has a mounting depth of 0.525" and an included SPST switch

 

[JimmyM]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

:welcome: . :twothumbs . . . :candle: . :thinking:

Any suggestions on the 2x MOSFETs ? I still have a couple of 2804s ?

But there is lots of room in the host so any really big ones that would work would be good ! ! !

Cheers Pete

The IRF2804 is perfect. It has very low Rds(on) and is good up to 40V.

 

[JimmyM]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

:twothumbsMmmmm, you're not wrong!
I charged the pack a few hours ago, and it now shows 34.5v (10 x A123)
I did attach a finned heatsink to the top of the FET as part of the original build, so I guess I should check temps with the 600w lamp fired up...... I'll let you know.

If you heatsink the 1KW version, I'll signoff on FAR excluding postage.
You do realize that this will be the highest power application of a Mag body size driver of any design. With that much amperage, the V2 is the better way to go. Also, I'm not sure how the board trace for the negative wire is going to react. I made it as wide as possible, but that's a lot of amps. To help remove this from the equation, you could solder the wire to the pad very close to pin of the MOSFET.

 

[littlejohnle]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

I'll take 2 x JM-SST No.
#B2-17 JM-SST &
#B2-18 JM-SST

For the amount of $56 US dollars.

Thank you.

 

[petrev]

Re: FOR SALE: JM-SST: PWM soft-starter Batch 2

OK

I'll take the last one just in case . . .

#B2-19 JM-SST

. . . blah blah blah.


Cheers Pete
:wave:

 

[JimmyM]

OK. Well I guess that about does it for Batch 2.
Can I get a show of hands for batch 3? If there's enough interest, I can build another batch.

 

[JimmyM]

Let's make it an even 20. The last one for general sale is up for grabs.

 

[pertinax]

Re: For Sale: JM-SST: PWM soft-starter Batch 2

Just for the record, I received mine and it works great. I'm running 19.2 volts into a 64458. Indeed, it will start fires.

No issues at all; using your board is a lot easier than trying to replace the stock switch for more current handling.

Pertinax