openinverter forum

will I get a nice fire if i connect a PTC like this rated to 230V to my 380V battery ?
Or will heat fast my car in the long winter ?

sfk wrote: ↑Mon Nov 25, 2019 5:44 pm I bought something like this PTC heater core - https://www.aliexpress.com/item/32815414254.html

I found one that closely matched the size of the heat exchange matrix in my car's existing heat/ventilation system.

There are different sizes, voltages, heat outputs etc.

HTB1O7SvRFXXXXaCXVXXxh4dFXXXA.jpeg
Specifications:
Rated voltage: 110V
Rated power: 1000W
Size(approx.): 140*102*26mm ( ripple length: about 96mm)

I got one of these last week and it looks just like a modern version of the used one I bought.
https://s.click.aliexpress.com/e/_DBFaueB

New on left and old used on right.
The quality of the plastic and potting compound appear to be identical, the wires are silicon covered, the nuts are A2 stainless and the terminals are platted copper (thanks for putting me right here remy_martian), the new one is around 10g heavier.
If this is fake is a damn good quality fake. The only thing I could say against it is the label has a few air bubbles.
It seems to draw approx 500mA initially then drop to 120mA

Stainless?

They are supposed to be silver plated copper studs, not shiny Chinesium. It also explains the added weight.

remy_martian wrote: ↑Fri Jul 22, 2022 5:58 am Stainless?

They are supposed to be silver plated copper studs, not shiny Chinesium. It also explains the added weight.

Sorry, my mistake. They ARE plated copper. I should have checked properly. I'll edit the original post
So I'm still looking for the issue here.
Maybe in a few months after putting it in a battery box buried in my conversion I might find out.

So would you prefer to use one of these or an older used one?
When I bought the older one I bought two and one of them turned out to have a high resistance of between 10R and 1kR, it was kinda all over the place.
Thankfully I checked BEFORE using it but if I hadn't who knows what would have happened.

I've got an Infineon FS800R07A2E3 IGBT module (same as BMW I3 and Leaf Gen3 inverters) and driver board combination sitting on my bench. It's complete with 900Amp LEM phase current sensors and possibly isolated voltage measurement.

Going by the markings, it came from a Dajun Tech inverter (Chinese motors and drives company) and they seem to be readily available as surplus.

I'd like to do some testing with it and work out the pinout. The first task is to find a matching connector. It seems to be1.27mm or 0.050" pitch 30 pin connector, with metal plates at each end for a latch arrangement. Whilst finding something that will plug in is pretty easy, it would be nice to find the correct mating connector that will actually lock in place.

Hi SciroccoEV

That's a Samtec Tiger Eye 1.27 pitch Connector.
Part Number for a 10 inch 30 pin Cable:
SFSD-15-28-H-10.00-DR-NDX

Mobert wrote: ↑Tue Aug 02, 2022 11:31 am That's a Samtec Tiger Eye 1.27 pitch Connector.
SFSD-15-28-H-10.00-DR-NDX

Perfect, thank you.

A start has made on that module over on ES: https://endless-sphere.com/forums/viewt ... 0&t=115094
Very tempting given the price.

A start has made on that module over on ES:

Thanks again. I had already identified the power supply and ground connections, but that gives me a small headstart.

Matching cable just delivered from RS.

I found a small industrial PTC heater on local electronic store and decided to open it up.

Before: After (with a connecting idea): 88x98x15mm without connector part.

It was originally connected like this:
1kw power (L1-N-NC-N-L1)
2kw power (L1-N-L1-N-L1)

JaniK wrote: ↑Fri Dec 30, 2022 4:56 pm I found a small industrial PTC heater on local electronic store and decided to open it up.

Before:
DSC_0079.JPG
After (with a connecting idea):
DSC_0099.JPG
88x98x15mm without connector part.

It was originally connected like this:
1kw power (L1-N-NC-N-L1)
2kw power (L1-N-L1-N-L1)

So how does a 230Vac heater element behave with 360Vdc connected across it and how would you control it?
I've ordered a 48V PTC heater and plan to run it off an ebike battery so hopefully a bit safer should something go wrong.

Alibro wrote: ↑Fri Dec 30, 2022 6:59 pm
So how does a 230Vac heater element behave with 360Vdc connected across it and how would you control it?
I've ordered a 48V PTC heater and plan to run it off an ebike battery so hopefully a bit safer should something go wrong.

The element has 4resistors, all had orig. 230Vac connected on full power normally in it, the way I connect it would be 2 series and 2 parallel. So I guess it Works like if it was on 2x230vac in series. I think someone on the forum made something similar from 2x 230vac car interior heaters. Not yet sure how to control. The heater had a mechanical thermostat and a 65°C thermal fuse next to element on the neutral line, so something similar maybe don't know yet

JaniK wrote: ↑Sat Dec 31, 2022 12:38 am The element has 4resistors, all had orig. 230Vac connected on full power normally in it, the way I connect it would be 2 series and 2 parallel. So I guess it Works like if it was on 2x230vac in series. I think someone on the forum made something similar from 2x 230vac car interior heaters. Not yet sure how to control. The heater had a mechanical thermostat and a 65°C thermal fuse next to element on the neutral line, so something similar maybe don't know yet

I see, so the heater elements will react the same to 360Vdc when doubled as they would to 240Vac when single. That is what I wasn't sure about.
Every time I go into my garage and look at the 2kW fan heater I wonder about using it the same way but I think I will try to use a 48V battery as I will be using it to drive the power steering anyway. It should be simple enough to build the battery a bit bigger to power a heater.

Have you seen this? The guy is a bit mad but it is interesting.

As far as the insulation rating of the ceramic PTC heater cores is concerned, the peak voltage of a 240VAC waveform is about 340VDC (VAC * SQRT 2). They're not designed for water exposure though. A droplet can bridge between the elements and cause problems.

The whole point of them being PTC, positive temperature coefficient, is that their resistance goes up with temperature at a rate that means they run at a pretty constant temperature across a wide voltage range. Even with no airflow, they'll typically limit to about 180C, which makes them a lot safer than a conventional metal heater element. The thermal cutout switch in portable heaters is required by the regulations, but mostly redundent in PTC heater. It also means that you can regulate heat output with airflow to a large degree and this was a common implementation in EV conversions back in the 90's. I found that I often wanted a high flow of warm air, rather than hot, so switched my cores in sections using low side mosfet drivers. The position of the heater control was read with a potentiometer.

Well as long as you keep elements covered against seting dust. I fiund out if you allow dust to settle on them they smell of burned socks .

arber333 wrote: ↑Sat Dec 31, 2022 4:16 pmI fiund out if you allow dust to settle on them they smell of burned socks .

Ahhyes, also known as "First time I've used the furnace this year" smell.

It's a bitter odor, a grumpy one, that reminds you that your house is just as grouchy about winter being here as you are.

This just arrived yesterday. I got it from Aliexpress and it's 48V 1000W
https://s.click.aliexpress.com/e/_DkGmk5Z for just over $16 delivered. It looks really nice so I might even order a second but will try this first to see how it goes.

What are you going to use to power them a 12v48v step up or wire them in series and see if the insulation is good enough?

rstevens81 wrote: ↑Mon Jan 02, 2023 2:35 pm What are you going to use to power them a 12v48v step up or wire them in series and see if the insulation is good enough?

I'm driving the power steering from an ebike type battery so will build the pack big enough to cope with this heater.
This is a very early test of the power steering pump.

So not exclusively ev related, but could be useful in some setups running lots of of throttle regen, as I’m running a gen2 Prius board I have no brake light output so figured something like this inertia brake light switch might be a good idea
https://www.louis-moto.co.uk/en/smart- ... n-10031139

Alibro wrote: ↑Sun Jan 01, 2023 10:58 am This just arrived yesterday.
IMG_20230101_105440126.jpgIMG_20230101_105431854.jpg

I got it from Aliexpress and it's 48V 1000W
https://s.click.aliexpress.com/e/_DkGmk5Z for just over $16 delivered. It looks really nice so I might even order a second but will try this first to see how it goes.

I may not need this after all as my newest Besty Jamie sent me this
https://ev-olution.yolasite.com/nissan- ... roller.php
It is a 'How to' for using the Nissan Leaf water heater I already have.
The parts I need are here now so will have a play with it and see how I get on.

Ev8 wrote: ↑Wed Feb 15, 2023 10:01 am So not exclusively ev related, but could be useful in some setups running lots of of throttle regen, as I’m running a gen2 Prius board I have no brake light output so figured something like this inertia brake light switch might be a good idea
https://www.louis-moto.co.uk/en/smart- ... n-10031139

I actually purchased and installed one of these and installed with a diode on the brake input so it only flashes the centre brake light when the accelerometer detects sufficient deceleration, I also temporarily hooked up a buzzer so I could tell what it was doing, I can report it seems to work very well at warning drivers behind me about slowing thanks to off pedal regen,

Ev8 wrote: ↑Fri Jun 23, 2023 6:17 am I actually purchased and installed one of these and installed with a diode on the brake input so it only flashes the centre brake light when the accelerometer detects sufficient deceleration, I also temporarily hooked up a buzzer so I could tell what it was doing, I can report it seems to work very well at warning drivers behind me about slowing thanks to off pedal regen,

I was looking at these for my electric motorbike, cars are suddenly on my back wheel when Im decelerating

Are these units adjustable.

I see there are cheaper copies on ebay

https://www.corsa-technic.com/item.php?item_id=1496

zippy500 wrote: ↑Thu Jun 29, 2023 2:20 pm I was looking at these for my electric motorbike, cars are suddenly on my back wheel when Im decelerating

Are these units adjustable.

I see there are cheaper copies on ebay

Only adjustment available is between solid or flashing light when decelerating, I never found any cheaper alternatives that actually used an accelerometer to trigger a brake light, there are lots of cheap brake light flashers on eBay but they just make an existing switch input into a flashing output, maybe you’ve found something else