Mosfet unknown failure ASCU+ASHU

[DustMagnet]

Originally Posted by GBBR

I blame only myself for my lack of insight towards this product, I should have researched about this product before promising a customer that I'll install it. now I have to find a few new ones, and install them in free for the customer. from now on I'm going to refuse any mosfet jobs as I think they are simply too risky.

My wallet hurts.

If you do get your hands on a Spectre, they are compatible with the ASHU.

[GBBR]

Originally Posted by DustMagnet

If you do get your hands on a Spectre, they are compatible with the ASHU.

Now to solve my wallet pain.

BTW if anyone reading this can get me that Spectre, I leave you with this gif

[Stealth]

The initial batch of Spectres sold out in record time.
Authorized dealers were allotted a very small number of units for sale, we're in the same waiting game as everyone else.

[Kos-Mos]

Originally Posted by GBBR

I blame only myself for my lack of insight towards this product, I should have researched about this product before promising a customer that I'll install it. now I have to find a few new ones, and install them in free for the customer. from now on I'm going to refuse any mosfet jobs as I think they are simply too risky.

My wallet hurts.

I know it might be a bit tricky, but do you know an electronic engineer?
Or even a college-level tech. This is the kind of programing/circuitry I used to do in college.

I would help you, but I don't have access to an oscilloscope...

By that I mean, if it's not the micro-controller that fried, it's probably just a bad design EMF/static-wise. FETs are extremely sensitive to this, even when in-circuit.
And they are extremely cheap to replace. So is a stocky diode to protect it (if you can fit it somewhere).

You would be looking at maybe 10$ in parts, if you can get a friend to diagnose the circuit.

[kaiu]

Originally Posted by coach

I've had the ASCU fail as well as the AWS raptor.

I have the new BTC spectre but have yet to have a chance to test it. Will probably install it into a drop in Lonex when I find the time.

+1

My AWS Stealth on the other hand works perfect still. Sometimes I'm afraid of getting a pricey mosfet now though since I am paranoid it will just be $100 bucks down the drain.

*No issues with any of my Gate Mosfets (Basic, AB and MERC) yet, one of my HH Airsoft Mosfets caught on fire, but the other 2 are working fine after 2 years.*

[Renegade)]

Originally Posted by DustMagnet

I have to admit, I've not heard good things about ASCUs.

Ill say this though, when it worked, I loved the ASCU!

The Spectre is pretty solid as well though I must admit. Still some fine tweeking to do though.

[Renegade)]

Originally Posted by coach

Ya, but I didn't pay for the Spectre. It was sent to me.

Hehehehehe aint being awesome great? My complimentary one works awesome as well!

[lurkingknight]

it sucks balls to drop that kind of coin on a unit that arrives in near dead condition. Of what I can see ascu has the highest failure rate of computerized mosfet units. Followed only by the raptor.. probably why AWS packed up shop.. though I can only speculate on that. The guy who designed the raptor I believe started up BTC and is the one behind specter and chimera, but those units have far better reliability so far.

I sort of remember somewhere some time ago I read that the design of the v1 ascu was lifted from the cheetah since it's open source. They went and changed a bunch of bits on it (to create higher margin) and bob's your uncle there you go, parts that are rated for lower power or just parts of lower quality were used to build them... but I don't think anyone has done a proper autopsy on one of them to find out why they're so fragile.

Originally Posted by GBBR

Update

Everything was tested.

In conclusion, Mosfet MUSTVE fried itself

I was really hoping there was some simple thing that was wrong and not the actual mosfet itself, I guess I got to swallow the hard truth that I must've bought a lemon and this kinda stuff just happens. I'm at a lost of words on how disappointed I am. Shame, now its time to shell out a MOSFET for a customer, LOL

[GBBR]

Originally Posted by Kos-Mos

I know it might be a bit tricky, but do you know an electronic engineer?
Or even a college-level tech. This is the kind of programing/circuitry I used to do in college.

I would help you, but I don't have access to an oscilloscope...

By that I mean, if it's not the micro-controller that fried, it's probably just a bad design EMF/static-wise. FETs are extremely sensitive to this, even when in-circuit.
And they are extremely cheap to replace. So is a stocky diode to protect it (if you can fit it somewhere).

You would be looking at maybe 10$ in parts, if you can get a friend to diagnose the circuit.

I understand that it may have been just a small blow resistor or something like that but I know nobody willing to bother daignosing it, or fixing a circuit like that. I'm ageist the diag, labpur, and parts may rack up to a price higher that the spectre.

[Kos-Mos]

Originally Posted by GBBR

I understand that it may have been just a small blow resistor or something like that but I know nobody willing to bother daignosing it, or fixing a circuit like that. I'm ageist the diag, labpur, and parts may rack up to a price higher that the spectre.

Well, the MOSFET is actually the most probable part to blow.
It "should" be the largest chip with only 3 tab (probably the middle one cut and not connected, as the back/heatsink is also connected to that).
It might however be a SO8-type chip (smallish, with 8 pins, 4 on each side). In that case, I would not be surprised it blown. Without active cooling (read a 1"x1" aluminum heatsink and a fan), it can't take over 10A really well.

What gen is the ASCU you have?

The pics I can find of gen3+ have the FETS (D2PAK) mounted on the same board as the trigger parts, and earlier have an external "power" module, probably housing the FETs.

On GEN3+, there does not seem to be any protection diode (other than the one built-into the FET chip). And there is not much space to add one in fact.
You could probably fit it here where they say to add tape, but you would need to dremel every rib in the mechbox side to clear some space (a decent diode is the same thickness as the FET chip).

As you can see, the metal tabs on the back of the FET are used to connect the drain/source (depending on the specs) with a larger connection and also dissipate the heat through the surface (and wires as they are connected there). If theses are not making a very good contact with the mechbox shell side, they will overheat and blow.

Sending you a PM.

[GBBR]

Thank you KOS-MOS

[GBBR]

BE JEALOUS

[cetane]

Originally Posted by GBBR

BE JEALOUS

I am :-/

[phloudernow]

According to the website, there is only a 0.1 percent failure rate which is pretty dang low compared to the ASCU imo. I have a Chimera in my Noveske and so far its performed amazingly. Havent had any issues with it so far though it is pretty brand spanking new as I put together my Noveske during the summer. Havent had time to program it though, I think i might have misplaced the menu some where.... but i can always download it off the website i guess haha

The Spectre is what i see to be the next gen AWS Raptor. basically the chimera shrunken down into a small unit for convenience...maybe i should have waited....installing the chimera was a pain in the ass and i had to get some help figuring out how to fit that thing in my stock tube LOL

I actually was considering the ASCU 3 but decided to use the Chimera instead. They released the Gen3+ units to compensate for some issues with the Gen3s....

Now im actually quite curious as to how their ASAR15's are going to be like...

[GBBR]

After putting up that mosfet I was bombarded with PM's about where and how much I got it for, unfortunately it was a private sale and I got it at a rock bottom price.

HOWEVER, all of you that are interested in this mosfet, stealth is selling them, check out this link
http://www.airsoftcanada.com/showpos...postcount=1059



I will be making a review thread after mine has been installed and also a side by side comparison between this mosfet and the other ones.