Using inverter for laptop + FS V2 with serial logging

[Dopey]

Hi All,
I recall that using an inverter to power a laptop/car PC was a big no no while the V2 was plugged in.... My question is, now that we are logging via the serial interface, is it still a no no? I have been wanting to put in a car pc for all my logging on track, but have put it off till I figure out a work around.

It would also look pretty cool to have a digital dash for the passengers to see

[Blacky]

Power inverters can cause problems. Sometimes you can go for months without a problem then some ground issues will show up and fry the inside of your V2. Using the serial connection for Wideband data makes no difference.

The problem occurs when different ground voltages exist between the laptop and the vehicle. If a difference exists, it flows through FlashScan as soon as FlashScan is connected between the laptop and the vehicle - sometimes frying components inside FlashScan.

You can power you laptop using a laptop power supply like the iGo Juice 70 (www.igo.com) We have used the Juice 70 for years with various laptops and FlashScan with no problems.

Regards
Paul

[mr.prick]

WOW!
this is news to me.
i have been using an inverter for almost 2 years without any problems.
sometimes if i turn it on after the car is running my RR will hiccup for a second,
i am also using the LC-1 which is notorious for its sensibility to ground offsets.
a good inverter should have surge protection and such.
what makes the iGo Juice 70 different from any other inverter
other than the extra features it has to power other devices?
how exactly would an inverter make problems for the V2?
shouldn`t the cig lighter be grounded/draw power
from the same place/source as the OBD2 port?
is there a way to test for inverter affects on the V2 before it`s "fried".
FYI
i have switched from battery to inverter
and noticed zero difference in logged data. (no anomalies)
on a very few instances at WOT, i have hit 12.5 battery volts(GM.VOLTS)
and have a steady average of 13.5-14 volts.

[Blacky]

I am not an electronics engineer, so I am only repeating what I've been "told" - it may need clarification form a areal electronics engineer.

The problem occurs when the inverter's ground is not pulled to the vehicle's ground. It can drift so that a voltage difference exists between the vehicle's chassis and the laptop's ground. If the difference is small (say 50mV or less) then there should not be a problem. If the difference is large, i.e. multiple volts, then when FlashScan is connected between the laptop and the vehicle, the ground path through FlashScan to the vehicle will conduct the voltage at zero resistance - which leads to a current surge through FlashScan as the grounds equalize.

Using a digital multimeter, measure the voltage difference between the USB port in your laptop and pins 4/5 on the OBDII connector. If they are the same (<50mV difference) then you may be ok.

One suggestion if you really must use a power inverter and don't have a multimeter handy is to do the following:
1. Connect the USB cable to the laptop while the laptop is being powered via the inverter.
2. Touch the other end of the USB cable to the vehicle's chassis to equalize any voltage difference between the laptop and the vehicle, then connect FlashScan.

Disclaimer: Even with the above precautions, EFILive does not recommend using power inverters due to the potential for damage. Use them at your own risk.

If Ross or Ira want to jump in and correct anything I've said, they will probably make more sense than me.

Regards
Paul

[Chuck CoW]

Hmmmm..... Very interesting...... Well, here's my observations....


For 2 or so years now, I've been using a pretty slick power supply for my HP laptops.......It plugs into the wall like a regular 110v laptop adaptor AND ALSO has a 12v cig lighter adapter.....

Either way you plug it in, it makes the laptop happy (obviously the 12v is only in the car) and I can tune for hours on end while the laptop stays fully charged...

Kinda neet.... I NEVER have a problem. Even with analog wideband hooked up.

Now, that being said..... A word of caution to ROADRUNNER users.

If using a Roadrunner, and a wideband (LM1 in my case) analog style..... the moment I put my 12v laptop adaptor to the laptop....You hear a pop and the car instantly shuts off....and the Roadrunner pretends it's dead like a dog on the side of the road. The car won't run until you do the RR MASTER RESET and reflash the cal.

Kinda spooked me the first time. On the phone crying like a baby to Craig for help.....

Lesson here....If you're gonna use that spaghetti of wires setup like I do.... It's best to fully change your booster pack and put it in the passenger compartment to run your inverter power supply.......

I don't think mine is actually an inverter....I believe it's just a transformer....Am I right?

Chuck CoW

[mr.prick]

Hmmmm..... Very interesting...... Well, here's my observations....


For 2 or so years now, I've been using a pretty slick power supply for my HP laptops.......It plugs into the wall like a regular 110v laptop adaptor AND ALSO has a 12v cig lighter adapter.....

Either way you plug it in, it makes the laptop happy (obviously the 12v is only in the car) and I can tune for hours on end while the laptop stays fully charged...

Kinda neet.... I NEVER have a problem. Even with analog wideband hooked up.

Now, that being said..... A word of caution to ROADRUNNER users.

If using a Roadrunner, and a wideband (LM1 in my case) analog style..... the moment I put my 12v laptop adaptor to the laptop....You hear a pop and the car instantly shuts off....and the Roadrunner pretends it's dead like a dog on the side of the road. The car won't run until you do the RR MASTER RESET and reflash the cal.

Kinda spooked me the first time. On the phone crying like a baby to Craig for help.....

Lesson here....If you're gonna use that spaghetti of wires setup like I do.... It's best to fully change your booster pack and put it in the passenger compartment to run your inverter power supply.......

I don't think mine is actually an inverter....I believe it's just a transformer....Am I right?

Chuck CoW

i always power up my inverter BEFORE i start the car
to avoid the the "belching" that i get with my RR.
the only time i get this disruption to the RR is
when the car is fully warmed up, and battery voltage drops,
and then turn on the inverter.

and to Paul:
i am not doubting what you said.
i just never thought damage could be done to the V2
from this type of usage and it kind of gives me pause for i have a lot
of money involved and would not intensionally risk damage to
my awesome hardware, but my experience with an inverter has been good.
i feel confident in my install because of the time span and,
all my power/grounds come from the vehicle harness
but i will do what you suggested and post the results.
maybe Moates will see this and have something to add.

[ntae]

I have been using a LIND adapter for the last 12 months and have not had a problem

http://www.lindelectronics.com/cgi-b...detail_product

[joecar]

When there many ground paths the possibility that they are not all at the same potential exists... for some people the differences in potentials is small (50mV or even 100mV)... but other people see greater difference (several volts or higher)... the ground loop current that flows equals the difference in potentials divided by the resistance between the potentials...

e.g. 2V/0.05Ω = 40A <--- this will cause something to pop!

Like I said... some people are lucky and some equipment has builtin protection.

[Cougar281]

You can power you laptop using a laptop power supply like the iGo Juice 70 (www.igo.com) We have used the Juice 70 for years with various laptops and FlashScan with no problems.

Regards
Paul

Just my $.03, I'd recommend staying away from the iGo products. I bought one and every 8-10 months, they died. I ended up going through five of them. I'd recommend checking with your PC manufacturer; HP has a nice AC/DC adapter that I use with my tablet (cost less than the iGo too!), I think Dell has one as well, and probably IBM. It wouldn't surprise me if all laptop manufacturers have one. The other advantage to using an OEM adapter is then if something happens to the laptop, the manufacturer can't say "Your aftermarket AC/DC adapter fried the computer. Warranty denied."

[mr.prick]