Changing the LVC in a 72v generic controller

[Ultraman]

This any use to you
http://zenid10.files.wordpress.com/2011 ... x12001.jpg

That's the photo I was looking for, thanks a heap Zenid. And thanks for shipping the controller out auraslip, looking forward to giving it a go.

[Reactor]

Hi everyone,
I have been following this closely and would like to change the LVC for 12S Lipo 3.3v per cell 12x 3.3 = 39.6v.

I have bought the controller and am just clarifying that all I need to do is put the correct SMD resistor value here http://min.us/lbz86GlV9

So I ended up installing a 2.2k resistor rather than the SMD resistors. Some napkin math calculation says it should hit LVC near 37v (or 2.3v per cell for 16s).

Some help in working this LVC calculation or the formula involved would be appreciated . I am guessing something around 2k.

[auraslip]

Sorry. I haven't been checking this thread.

I forget the math... IIRC LVC for 72v SLA is... I don't know

but figure that out and then find the ratio between it and the LVC you want (39.6v)

and then use that ratio to figure out what resistor value you need. FYI, you may need to alter or remove the voltage divider resistor to get the value you need.

Sorry can't help more. Hung over as shit.

[Zenid]

Anyways, rather than just fixing the LVC with a resistor, I installed a 5k pot inside the controller and set it to run 72v. This way you can adjust the LVC with ease if need be. I finally shipped today btw.

I don't quite understand why they put that extra SMD slot on the board: Adding a resistor in parallel will only raise the value of the LVC, so why did they include a blank space in parallel as part of the voltage divider? I know for a fact that these controllers don't take kindly to overvolting...
http://zenid10.wordpress.com/2011/09/03/meltdown/
I've finally got round to opening one of my new batch of controllers up and can see exactly what you're talking about. But I've found alternative mounting points that might make things a little easier, and think I'll go with a 1.8KΩ setting for the 48V LVC, and a 1.5KΩ setting for a 60V LVC. I'll use a pot for this like yourself. Congrats again on nailing this.

[auraslip]

extra smd slot just gives them more options. this board could probably be used with voltages from 24v-100v depending on the build.

Good to know that the fets are only rated at 75v. I honestly don't know why these controllers are so popular. For the amount of work you have to put into them, and for the quality of them.... better to just spend twice as much and get a programmable controller.

I need to look into importing some generic infenions.

[The Mighty Volt]

extra smd slot just gives them more options. this board could probably be used with voltages from 24v-100v depending on the build.

Good to know that the fets are only rated at 75v. I honestly don't know why these controllers are so popular. For the amount of work you have to put into them, and for the quality of them.... better to just spend twice as much and get a programmable controller.

I need to look into importing some generic infenions.

I'd be more than interested in that.

[wesnewell]

You people are really screwed up. The fets in the Hua Tong 72V 1500W controller are not 75V, but 100V fets. Zenids meltdown link showing the controller is not even a Hua Tong 72V 1500W controller. The Hua Tong 72V 1500W controller does not use P75NF75 75V fets. If it did, I would have smoked them the first time I used a 100V pack. It uses 100V fets, 15 of them.

[bobale]

The fets in the Hua Tong 72V 1500W controller are not 75V, but 100V fets. Zenids meltdown link showing the controller is not even a Hua Tong 72V 1500W controller.

I second that. Older HuaTongs had 4410, and newer have 4710, so both 100V rated. Caps also.

BTW, he said this about controller he blown with overvolting:

The LiFePO4 bank also spends for more of its discharge at above nominal voltage, so I was seldom going below 80V, and running the bike typically at 81-84V. The fact that it survived two weeks running at about 115% of its rated value – continuing to work even after it began melting – is a testament to how rugged these units are…

[auraslip]

You people are really screwed up. The fets in the Hua Tong 72V 1500W controller are not 75V, but 100V fets.

extra smd slot just gives them more options. this board could probably be used with voltages from 24v-100v depending on the build.

The controllers are probably just built with what ever they can get the cheapest that day. This is china.

[wesnewell]

Even so, they wouldn't use 75V fets in a 72V controller. Even an SLA 72V battery pack has more than 75V output. Closer to 81V.

[auraslip]

Even an SLA 72V battery pack has more than 75V output. Closer to 81V.

This is true.

But as I said; made in china.

[Zenid]

You people are really screwed up. The fets in the Hua Tong 72V 1500W controller are not 75V, but 100V fets. Zenids meltdown link showing the controller is not even a Hua Tong 72V 1500W controller. The Hua Tong 72V 1500W controller does not use P75NF75 75V fets. If it did, I would have smoked them the first time I used a 100V pack. It uses 100V fets, 15 of them.

The Hua Tong 72V 1500W controllers *I* have definitely have P75NF75 FETs. I opened them up and took photos to find out:
http://zenid10.files.wordpress.com/2011/03/fet1-1600x1200.jpg

The melted one in the photo on my blog is a Hua Tong controller too, but with one of the stickers removed and a big "chatparts.com" sticker put in its place. The other, distinctive "72V" sticker with the cantonese all over it remains though. I know it is a Hua Tong controller because they are all sealed with little holographic stickers saying "Hua Tong" when you hold them up to the light. In fact you can see the sticker in the picture:
http://zenid10.files.wordpress.com/2011/09/pr04-1600x1200.jpg
Full article:http://zenid10.wordpress.com/2011/09/03/meltdown/

I can take close-up of it if you like, though? I could also open this one up and check that the FETs in this are the same as in the other one. It does seem impressive that they would survive such abuse...

However, as auraslip says, "this is China". You can't believe for sure that any markings genuinely reflect what they're stamped on, and tolerances vary wildy. Like ratings on CPUs, these FETs might just be 100V ones that flunked quality control and got classified as "75V" because that's the role they should play to minimise the risk of pissed off customers complaining about dead controllers...

[wesnewell]

I'm not doubting your fets, but that it isn't the Hua Tong 72V 1500W controller we are talking about. It doesn't even look close to it. The controller you show has 2 groups of wires coming out of the end, and the Hua Tong 72V 1500W controller we are discussing only has a single outlet. It's more likely the controller you picture is the original 60V controller that came in the scooter you have. No manufacturer is dumb enough to use 75V fets in a system that at minimum is designed for 81V. Anyone else here look at your fets and have 75V fets in your controller? All I've heard of is 4410's and 4710's in the newer board.

[Zenid]

I'm not doubting your fets, but that it isn't the Hua Tong 72V 1500W controller we are talking about. It doesn't even look close to it. The controller you show has 2 groups of wires coming out of the end, and the Hua Tong 72V 1500W controller we are discussing only has a single outlet.

Yes. I wasn't sure about this myself, but the stickers and the little holographic seal both say "Hua Tong".

Yes. There is a two-hole end-plates on this version, but we're back to the whole "This is China" thing again. I'm on my third batch of these things and they are constantly changing. The power wires of my latest batch are ring connectors all of sudden, rather than the spades in that three-way mini-connector that they used be part of:
http://zenid10.wordpress.com/category/3-components-specs/3-4-controllers/3-4-1-generic-72v-controller/

And while my first two Hua Tongs - the melted "chatparts.com" one and the one in the picture above - both had an orange cruise control wire, this was mysteriously dropped from one of the batches too.

It really doesn't make a whole lot of difference, as I don't think either of us really knows what "a Hua Tong" really means definitively. Any of these could be authentic or they could be knock-offs. I'm calling them all "Hua Tong" because they have the stickers and the holographic seal on them saying "Hua Tong".

The bottom line is these things - for what you pay - seem to work well and not do a bad job at all, even surviving some pretty horrible abuse at times. If nothing else they're great to have as spares to use for if your nice LYEN or eCrazyman controller blows a FET as mine did...

P.S: No, that melted one wasn't the controller that came with the my bike. It was a "72V 1500W" one I bought on-line. My original was a 48V controller that I sold on to someone else whose own had broken down...

[wesnewell]

Hua Tong makes lots of different controllers. They make 48V, 60V, 72V, and probably other voltages. One person said they had a 48V version that had 63V caps. I don't recall if he mentioned the mosfets on it. But if all the controllers you got were marked as 72V controllers with 75V mosfets then you should submit a complaint against whomever you bought them from since they can't be rated as 72V controllers with 75V fets.

[Zenid]

But if all the controllers you got were marked as 72V controllers with 75V mosfets then you should submit a complaint against whomever you bought them {...}

What's to complain about? The controllers work, that's all that matters. What do you expect for $35-a-pop wholesale? I've had haircuts more expensive than that. If one breaks, I'll just chuck it in the bin and get another out the box.

If you don't want one then don't buy one.

[wesnewell]

But if all the controllers you got were marked as 72V controllers with 75V mosfets then you should submit a complaint against whomever you bought them {...}

What's to complain about? The controllers work, that's all that matters. What do you expect for $35-a-pop wholesale? I've had haircuts more expensive than that. If one breaks, I'll just chuck it in the bin and get another out the box.

If you don't want one then don't buy one.

What's to complain about? How about it's not built to specs! I don't care if it $5 or $500. It's out and out fraud. And don't worry, I won't buy one of those. The 2 I have now both have 100V mosfets. Just curious what voltage you are running them at, I run mine at 100V. Give that a shot for a while and let me know how it works out for you.

[The Mighty Volt]

Hua Tong makes lots of different controllers. They make 48V, 60V, 72V, and probably other voltages. One person said they had a 48V version that had 63V caps. I don't recall if he mentioned the mosfets on it. But if all the controllers you got were marked as 72V controllers with 75V mosfets then you should submit a complaint against whomever you bought them from since they can't be rated as 72V controllers with 75V fets.

I think that might have been me. I got my controller with a 48v 1500w rated Moped Motor, which is what Zenids Hua-Tong controller was feeding. It's a 15 Mosfet, 4410 spec, with 63v caps. The 4410 Fet's are 75v rated.

[Zenid]

Just curious what voltage you are running them at, I run mine at 100V. Give that a shot for a while and let me know how it works out for you.

I was running the thing with a 72V SLA bank for months with no problems, as do many other people. When I moved up to Lithium I overvolted one at 80-84V for a couple of weeks to see how far I could push it. It got hot enough to melt the grommets and silicone sealant, but still worked. I call that a good, working 72V controller.

As for trying to run it at 100V - why would I do a silly thing like that? It's a 72V controller, - okay below 80V, but overheats at above this. For a 100V bank I would use my Lyen's controller with the nice, IRFB 4110 MOSFETs. The quality one that I paid four times as much for...

[bobale]

As for trying to run it at 100V - why would I do a silly thing like that?.

Well, why not? I like pushing thing to their limits (sometimes beyond ), especially if they are cheap and/or easily repairable. Caps and FETs in ours HuaTong controllers are rated for 100V, so 100V would be pushing it really hard, but 90V would live you with a nice margin.

I run mine at 90V, and will run it like that as long as it holds up. It was only $37, so screw it. And just for the record, @90V it runs a lot cooler than stock 9FET Infineon @57V .

[Zenid]

Well, why not? I like pushing thing to their limits (sometimes beyond ), especially if they are cheap and/or easily repairable. Caps and FETs in ours HuaTong controllers are rated for 100V, so 100V would be pushing it really hard, but 90V would live you with a nice margin.

The ones in mine are only 75V rated, that's what this debate has been about.
Like I said, I like pushing thing to their limits too:
http://endless-sphere.com/forums/viewtopic.php?f=2&t=26306&p=466140#p465969
I overvolted one to 80-84V and it started to melt...
http://zenid10.wordpress.com/2011/09/03/meltdown/

[wesnewell]

That's what I'm talking about. A 72V controller shouldn't get that hot at only 84V. Mine runs cool as a cucumber on 100V. And for The Mighty volt, 4410 fets are rated for 100V not 75V.

[Zenid]

That's what I'm talking about. A 72V controller shouldn't get that hot at only 84V. Mine runs cool as a cucumber on 100V. And for The Mighty volt, 4410 fets are rated for 100V not 75V.

That's because it has 100V rated FETS and should therefore be runnable at 100V. Just like my Lyens controller.

A "72V" controller gets that hot at 84V because - as I ascertained from experiment - it is only suitable to be run at under 80V (at least this one from this batch).

Do you not understand that is NO SUCH THING as a "75V" or "100V" FET per se? These are just nominal ratings given based on their ability to run at these voltages while effectively dissipating heat. Quality of components varies. Some behave better than their rated values and others worse. If they perform well at higher voltages, someone stamps it with one little number, if they perform more poorly and get hot, they get stamped with another little number. But they are often exactly the same components, from exactly the same production process that SHOULD perform the same. That's the joy of statistical variation in quality: the whole thing is crap shoot.

You can "shoulda" til the cows come home, but at the end of the day you pay your money, you take your chances. Sometimes you end up with great stuff for near nothing, sometimes you pay big bucks and end up with shit. Get used to it.

And, again, "This is China!"

[The Mighty Volt]

@Wesnewell

I made a mistake. I have I407 Mosfets in mine, rated for 75v, in a 48v rated controller, which is acceptable.

The ratings are only nominal.

For instance, a 100v rated capacitor is rated to 100v, give or take 10volts.

So it could be 90 or it could be 110.

That's why a 72v controller has 100v capacitors, a 100v controller has 150v capacitors etc.

These controllers should be a cheap platform for us to work off.

Nothing more.

[wesnewell]

A "72V" controller gets that hot at 84V because - as I ascertained from experiment - it is only suitable to be run at under 80V (at least this one from this batch).

Do you understand that a 72V SLA battery pack in good condition will charge to over 80V? That's why it shouldn't be rated as a 72V controller using 75V fets. These aren't batteries, and the ratings aren't nominal ratings.