# [EVDL] PFC wired, what next?



## EVDL List (Jul 27, 2007)

Today I got the parts from Lowes and built a
"patch cord" for my PFC-30 to use my "old style"
30a 3-wire dryer outlet.  It said in the PFC manual not
to run it unloaded, but didn't specify a minimum
load, so I put a voltmeter on it. It said 27 volts.

I didn't get my tuner pot scredriver yet,
but I have questions -
I have TS 100Ah + Elithion. The BMS are installed
but the 50 wires for shutting the charger are not in yet.
But I have one cell reading .2 v lower than the others,
so I would like to charge. Is it OK to charge without
the charger shutoff in place? i.e., with the regulators just
bypass the full cells?

Should I just hook up 8 cells, which should charge at about 27V?

Or should I just search my house for some battery charger
or wall wart that puts out a voltage to match N cells?

Thanks alot everyone
Seth
PS If this sharing dryer plug lasts for long, the next
thing will need to be adding pull handles for the plugs...

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## EVDL List (Jul 27, 2007)

Hi Seth,

Don't charge at the pack level without a BMS.
Especially when you *know* the pack is out of balance.

You can charge a few cells without a BMS though.

For 8 cells, set the max charge voltage to 7*3.3+4 = 27.1v
Since the worst case is 7 of the cells at 3.3v, and one full one rising up
to 4v.

You can apply this method to any number of cells, its just the 0.7V of
margin gets to small when you start trying to charge more than around 8
cells.

Matt 

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf
Of Seth Rothenberg
Sent: Wednesday, 3 February 2010 2:39 PM
To: Electric Vehicle Discussion List
Subject: [EVDL] PFC wired, what next?

Today I got the parts from Lowes and built a "patch cord" for my PFC-30 to
use my "old style"
30a 3-wire dryer outlet. It said in the PFC manual not
to run it unloaded, but didn't specify a minimum load, so I put a voltmeter
on it. It said 27 volts.

I didn't get my tuner pot scredriver yet, but I have questions - I have TS
100Ah + Elithion. The BMS are installed but the 50 wires for shutting the
charger are not in yet.
But I have one cell reading .2 v lower than the others,
so I would like to charge. Is it OK to charge without
the charger shutoff in place? i.e., with the regulators just bypass the
full cells?

Should I just hook up 8 cells, which should charge at about 27V?

Or should I just search my house for some battery charger or wall wart that
puts out a voltage to match N cells?

Thanks alot everyone
Seth
PS If this sharing dryer plug lasts for long, the next thing will need to be
adding pull handles for the plugs...

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## EVDL List (Jul 27, 2007)

> Seth Rothenberg wrote:
> 
> > It said in the PFC manual not
> > to run it unloaded, but didn't specify a minimum
> ...


----------



## EVDL List (Jul 27, 2007)

> Seth Rothenberg wrote:
> 
> > Should I just hook up 8 cells, which should charge at about 27V?
> 
> ...


----------



## EVDL List (Jul 27, 2007)

Thanks everyone. I am not considering
charging without BMS. Only without
the circuit to automatically turn off the charger.
Will babysit it.

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## EVDL List (Jul 27, 2007)

> Doug Weathers <[email protected]> wrote:
> >
> > Manzanita Micro $200 to fix it. ("Blew it up" means turning the
> > voltage pot didn't affect output voltage or current very much; it
> ...


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## EVDL List (Jul 27, 2007)

Really? This is kinda scary. Lets say some fault (other than the 
charger) causes a fuse between the charger and battery pack to blow. Or 
after servicing the pack, just plain forget to hook the charger up. 
Either way, go to charge and charger gets fried? Seems like this would 
result in a rather high mortality rate for the chargers...
(I used to have one; someone I know currently uses one)



> Doug Weathers wrote:
> > Look out! They really mean "Don't run it unloaded". I blew mine up
> > that way (powered it up with nothing on the output) and had to pay
> > Manzanita Micro $200 to fix it. ...
> ...


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## EVDL List (Jul 27, 2007)

The dummy load reccommended to me by the man himself is to buy a few of
those ceramic light sockets (1 per 100V of pack ) and wire them in
series. Screw in 150W flood lamps. and you have a constant current load
to work with.
>


> Seth Rothenberg wrote:
> >
> >
> >> > Should I just hook up 8 cells, which should charge at about 27V?
> ...


----------



## EVDL List (Jul 27, 2007)

> Jeff Shanab <[email protected]> wrote:
> > The dummy load reccommended to me by the man himself is to buy a few of
> > those ceramic light sockets (1 per 100V of pack ) and wire them in
> > series. Screw in 150W flood lamps. and you have a constant current load
> ...


----------



## EVDL List (Jul 27, 2007)

When the current knob is turned WAY down, I also hear a "sizzling" sound 
from my PFC-20. It's actually more of a soft white noise. I believe this 
is an internal wire, inductor, or transformer that buzzes (vibrates) with 
the switching frequency of the charger. I listen for it when opportunity 
charging - lets me turn the current down so I don't blow a 15A breaker 
without having to get out a current meter.


> The only peculiarity is that the charger cuts back due to overtemp
> (the yellow light is blinking and the ams drop significantly) even
> when the ambient temperature is in the 60F range.
>

This doesn't sound normal, unless the charger doesn't have good airflow or 
one of the fans is broken. Even enclosed in the *small* trunk of my car 
with an ambient of 80F I don't get thermal cutback (but the fans get MUCH 
louder!)

-Adrian




>> Manzanita Micro $200 to fix it. ("Blew it up" means turning the
>> voltage pot didn't affect output voltage or current very much; it
>> just caused a quiet hissing/sizzling noise to get louder or softer.)
>>
>
> I have a question for all you Manzanita Micro users. I have a PFC-30
> and it seems to be working fine. Charges to the voltage I need. Tapers
> down as I expect. Does everything it should.
>
> I do notice though, when I first turn it on, the "quiet
> hissing/sizzling noise" when it first fires up. Mine immediately ramps
> up to about 25 amps as measured by an analog meter wired into my car.
> The sound can also be characterized lie bacon frying. It seems to go
> away over time, but I'm not 100% sure. Maybe the fan noises cover it
> up.
>
>

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## EVDL List (Jul 27, 2007)

> Jim Coate wrote:
> 
> > Really?
> 
> ...


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## EVDL List (Jul 27, 2007)

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## EVDL List (Jul 27, 2007)

My plan is to use a 240VAC 40A solid state relay in series with the AC power to the PFC-20. I'll leave the Anderson connector on the DC side permanently connected to the 500A fuses that are the first things out of the pack on pos and neg (except for the link 10 shunt on the neg side). There will be a 400A Heinemann breaker between front (4 batts) and rear (8 batts) boxes, and this breaker has aux contacts which I will use to enable the SSR. So if the breaker is open, the PFC can't be powered up.

Any hidden drawbacks to this strategy?

- Gene


-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Doug Weathers
Sent: Wednesday, February 03, 2010 4:34 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] PFC wired, what next?




> Jim Coate wrote:
> 
> > Really?
> 
> ...


----------



## EVDL List (Jul 27, 2007)

> Evan Tuer wrote:
> 
> > The problem is that there's not much which can (affordably)
> > protect against the output becoming suddenly unloaded. Not
> ...


----------



## EVDL List (Jul 27, 2007)

Simple answer - don't put a fuse there! You really don't need it, anyway. 
The PFC-20 in the Mustang has an output fuse.

Joseph H. Strubhar

Web: www.gremcoinc.com

E-mail: [email protected]


----- Original Message ----- 
From: "Roger Stockton" <[email protected]>
To: "'Electric Vehicle Discussion List'" <[email protected]>
Sent: Wednesday, February 03, 2010 6:16 PM
Subject: Re: [EVDL] PFC wired, what next?




> > Evan Tuer wrote:
> >
> >> The problem is that there's not much which can (affordably)
> >> protect against the output becoming suddenly unloaded. Not
> ...


----------



## EVDL List (Jul 27, 2007)

> Doug Weathers wrote:
> 
> >>
> >> It said in the PFC manual not
> ...


----------



## EVDL List (Jul 27, 2007)

> Joe wrote:
> 
> > Simple answer - don't put a fuse there! You really don't need
> > it, anyway.
> ...


----------



## EVDL List (Jul 27, 2007)

I have talked to rich lately and there have been improvements to the
control board.
Disconnecting under load is still an issue and I admit I did it once a
long time ago at a low amperage with no damage. (Elbow bumped center of
pack disconnect)

I wonder if an industrial pilot lamp across the output would suffice.
Maybe it can be wired in such a way that it lights when the circuit is
open? (tricky, but not impossible)

The problem with such a thing is what voltage? There are so many
different pack voltages with the PFC, It is not "set"

ANyway, check out their site and talk to rich. If you are replacing the
board, get the new version ~$150.00

>


> Doug Weathers <[email protected]> wrote:
> >
> >
> >> > Well, it killed mine. The guys at Manzanita Micro don't seem to
> ...


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## EVDL List (Jul 27, 2007)

> John G. Lussmyer wrote:
> 
> > Actually, if the output fuse on a PFC charger blows - there
> > is some other problem. Like dropping a wrench across the terminals.
> ...


----------



## EVDL List (Jul 27, 2007)

No, the fuse that is built into the charger takes care of that - I know, 
because I had the one in the Mustang wired up wrong, and blew 2 fuses before 
finding out what the problem was!

It won't shut the charger down completely, just the output isn't operating 
after the fuse blows. That is, there is nothing going into the pack, 
although the lights are still on, and the fans are still working.

Joseph H. Strubhar

Web: www.gremcoinc.com

E-mail: [email protected]


----- Original Message ----- 
From: "Roger Stockton" <[email protected]>
To: "'Electric Vehicle Discussion List'" <[email protected]>
Sent: Thursday, February 04, 2010 7:55 AM
Subject: Re: [EVDL] PFC wired, what next?




> > Joe wrote:
> >
> >> Simple answer - don't put a fuse there! You really don't need
> >> it, anyway.
> ...


----------



## EVDL List (Jul 27, 2007)

> Joe wrote:
> 
> > No, the fuse that is built into the charger takes care of
> > that - I know, because I had the one in the Mustang wired up
> ...


----------



## EVDL List (Jul 27, 2007)

> On 4 Feb 2010 at 10:06, Roger Heuckeroth wrote:
> 
> > That sounds like a design flaw to me. I know Manzanita is considered
> > one of the best chargers out there, so it surprises me that they would
> ...


----------



## EVDL List (Jul 27, 2007)

It is basically just a PFC front end feeding directly into the battery? This
would mean that the output can never be below the peak of the mains. Do they
run on 220V? or only on 110V?
I have designed PFC front ends and understand some of the
challenges, I may be able to help identify what the problem is.

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf
Of EVDL Administrator
Sent: Friday, February 05, 2010 6:30 PM
To: Electric Vehicle Discussion List
Subject: Re: [EVDL] PFC wired, what next?



> On 4 Feb 2010 at 10:06, Roger Heuckeroth wrote:
> 
> > That sounds like a design flaw to me. I know Manzanita is considered
> > one of the best chargers out there, so it surprises me that they would
> ...


----------



## EVDL List (Jul 27, 2007)

----- Original Message ----- 
From: "George Tyler" <[email protected]>
To: "'Electric Vehicle Discussion List'" <[email protected]>
Sent: Thursday, February 04, 2010 9:59 PM
Subject: Re: [EVDL] PFC wired, what next?


> It is basically just a PFC front end feeding directly into the battery? 
> This
> would mean that the output can never be below the peak of the mains. Do 
> they
> run on 220V? or only on 110V?
> I have designed PFC front ends and understand some of the
> challenges, I may be able

The Manzanita PFC charger is just one component in a installation of a 
charger system. The technician must be able to install all the other 
sub-components that are needed as per the specifications of a design 
engineer and/or need to have the knowledge to install a complete system.

This charger will accept any input voltage from 80 to 250 volts AC and have 
any output from 12 to 425 volts DC. To design a complete system using this 
component, it is recommended to install a DC amp and volt meter on the DC 
side and on the AC side a GFI receptacle or a on-board GFI chassis mount 
circuit breaker as a minimum installation.

It is also prefer to install battery regulators that are design by Manzanita 
that can be interface with this charger.

I have added a AC volt and amp meter, a ampere-hour meter, a watt meter, a 
240 VAC 50 amp GFI on board chassis circuit breaker, a AC magnetic contactor 
on the incoming AC lines, a DC contactor on the charger output, external fan 
blower to cool to bring in filter cool air for the charger, a explosion and 
acid proof exhaust fan for the battery box, fresh filter air inlets and made 
the charger and battery enclosure compartments with a non-conductive 
material as to isolated these components from the vehicle structure itself.

The most inportant component I first added to the EV, even before I had the 
PFC charge is two contactors that disconnected the battery from the main 
contactor and controller. I have burn out a DC-DC rotary converter, arc the 
commentator of the motor and some components of the controller by 
suppressing the higher charging current on these components.

I only ground the charger case with the incoming electrical ground circuit 
and not the vehicle. This is the same technique we use when we install a 
isolated ground system in a building that requires it.

If you install a isolated system using the above method and/or using as 
double insulated compartments, we must install a line fault or sometimes 
call a ground detection system. (not a GFI). This unit detects if any of 
the line conductors including the electrical ground wire is connected to a 
conductive structure that is not to be ground or have a non-ground conductor 
connected to it.

If a any of the line or ground detection circuit raises to a un-safe level, 
then it will turn off the AC contactor and the the DC contactor in that 
order. Also if the battery ventilation fails, the charging system is also 
disconnected in that order.

Even if doing all of the above, and if a user is touching any of the battery 
terminals while charging and standing on a earth ground bare naked, then 
they have a problem if you not using a GFI. You always wear and/or have 
safety equipment when working on energized equipment.

Roland 

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## EVDL List (Jul 27, 2007)

The EVDL Admin wrote -

> = They aren't isolated from the mains. A ground fault from battery to
> chassis, combined with an open ground in the supply, can mean shock or 
> even
> electrocution. They don't even have built-in GFIs. The instructions 
> direct
> you to install one upstream of the charger, but I wonder how many do.
> Fortunately, such a thing isn't common.

What ARE some of the solutions to the GFI problem that people have used?

I was thinking of using this Leviton 240 GFI (# 230405418587 on Ebay) with a 
relay http://www.onlinecomponents.com/buy/PB-TYCO/PRD-3AP4-120/ (which if 
you look at the pdf data sheet says that if you use the box lugs as main 
terminals, it is rated for 50amps at 277vac)

And put inline amp/voltage meters to see what is going in and what is going 
out.
How does that sound?

Rush Dougherty
Tucson AZ 

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## EVDL List (Jul 27, 2007)

That what I did. Install a 50 amp GFI circuit breaker on board. I use the 
250 volt rating but any voltage over that is ok. The Square D plug on 
breaker with box lugs that plug into a small 2 bar open type panel that is 
chassis mounted.

You do not have to use a AC contactor in the AC line if you are using a GFI 
on board breaker if you are not going to isolated the charger and batteries 
from the AC grounded frame of the vehicle.

If you are going to isolated the charger and batteries from a non-grounded 
frame of the vehicle, this requires a ground detection system that detects 
any leakage to non-grounded enclosure. If any fault, it then opens a AC 
contactor on the incoming AC lines.

Roland




----- Original Message ----- 
From: "Rush" <[email protected]>
To: "Electric Vehicle Discussion List" <[email protected]>
Sent: Thursday, February 04, 2010 10:36 PM
Subject: Re: [EVDL] PFC wired, what next?


> The EVDL Admin wrote -
>
> > = They aren't isolated from the mains. A ground fault from battery to
> > chassis, combined with an open ground in the supply, can mean shock or
> > even
> > electrocution. They don't even have built-in GFIs. The instructions
> > direct
> > you to install one upstream of the charger, but I wonder how many do.
> > Fortunately, such a thing isn't common.
>
> What ARE some of the solutions to the GFI problem that people have used?
>
> I was thinking of using this Leviton 240 GFI (# 230405418587 on Ebay) with 
> a
> relay http://www.onlinecomponents.com/buy/PB-TYCO/PRD-3AP4-120/ (which if
> you look at the pdf data sheet says that if you use the box lugs as main
> terminals, it is rated for 50amps at 277vac)
>
> And put inline amp/voltage meters to see what is going in and what is 
> going
> out.
> How does that sound?
>
> Rush Dougherty
> Tucson AZ
>
> _______________________________________________
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>
> 

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## EVDL List (Jul 27, 2007)

> Roger Stockton wrote:
> > If the fuse opens because an internal fault has already occurred
> > inside the charger, that's one thing, but it should not be acceptable
> > that an otherwise healthy charger can fail simply because the output
> ...


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## EVDL List (Jul 27, 2007)

What about a Jacobs Ladder mounted on top of the charger, ala
Frankensteins laboratory? Most people would just think it's just
another "electrical thingy", but when you have problem, bzzzzzzzzt,
you know it. Could you design one to work with the voltages you get
when the inductor unloads?

Dave Cover, asking the stupid questions so you don't have to



> Lee Hart <[email protected]> wrote:
> > Roger Stockton wrote:
> >> If the fuse opens because an internal fault has already occurred
> >> inside the charger, that's one thing, but it should not be acceptable
> ...


----------



## EVDL List (Jul 27, 2007)

There's a few problems with using a spark gap like a Jacob's Ladder.

The ones you see in movies are thousands or tens of thousands of
volts. With silicon that can only handle hundreds of volts, you need a
very small gap, probably less than 1mm.

Also, it won't be precise enough. As the humidity of the air changes
or grime and debris get onto the contacts, the voltage needed to cause
an arc will change quite a bit, so it might trip at a safe battery
voltage or not trip until after the silicon fried.

Silicon devices such as zener diodes can perform the function and
start conducting when the voltage gets too high, but they have to be
able to handle dissipating the energy stored in the inductor. You'd
need some big, expensive silicon to do it that way.

If the cost of output capacitors is too high, a crowbar circuit like
Lee described seems like a much better solution than a spark gap or
clamping diodes. The crowbar can trigger at a consistent enough
voltage to protect the silicon without impeding normal operation,
making it work better than a spark gap. A crowbar or clamping diodes
each need to handle the same inductor current, but the crowbar has
about 100 times lower voltage across it, so the power is 100 times
lower. That makes it much less expensive to design a reliable crowbar
circuit than to use clamping diodes.

You still need a fuse between the crowbar and the output to keep the
batteries from discharging through the crowbar if the crowbar somehow
trips while the batteries are connected. However, if the crowbar trips
because of an open-circuit output, the fuse wouldn't blow, so usually
it would protect the charger with no bad side effects.

It would add some cost, though, and when Rich asked people what they
wanted, they said cheap and powerful, so that's what he built.

-Morgan LaMoore



> dave cover <[email protected]> wrote:
> > What about a Jacobs Ladder mounted on top of the charger, ala
> > Frankensteins laboratory? Most people would just think it's just
> > another "electrical thingy", but when you have problem, bzzzzzzzzt,
> ...


----------



## EVDL List (Jul 27, 2007)

> Lee Hart wrote:
> 
> > I think the fundamental problem is that there is a large
> > inductor in the PFC charger. When a high current is flowing
> ...


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