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JBD 4S 200A BMS

I also have one. There is no heater option in the app, at least not on the IOS version.

I did some testing with mine (SP04S03A Partno 16240017), with the heater terminal connected (screw connector), just as the picture from @RV Truck Camper

I have set the charge under temp to 3, release at 5.

For testing, I've connected a 12V 50W H7 halogen bulb between H and battery positive.

With no charge, nothing happens, also not when you reach the set threshold for the low temp disconnect.

When you apply charge, things are differently. With the temp above set under temp, it just charges, nothing special.
If the temperature of ANY of the sensors is below the set temp:
- Charging stops due to low temp
- H connector is switched ON, 12V between H and battery + (thus enabling heater), as long as the 'charge under temp' is not released
- When the temp rises above the set release value (and release delay is expired), heating is disabled and charging restarts. (Charge under temp is released)

Exactly the behaviour you want, there is no need to have the heating running without charge.

Thus: Conditions to enable the heater
- Temp of any of the sensors has to be below set temp (causing a low temp charge disconnect)
- Charge voltage must be applied (otherwise the low temp charge disconnect isn't triggered)
- Charging starts once the release threshold temp is reached, (+ delay value expires) , heater is disconnected

As for the temperature sensors: Mine had 2, and they don't have all to be in low temp: A single sensor detecting too low will work.

Note: I did load the previous settings from my 120A BMS. That one had less temperature sensors, so I had to enable NTC 1/2/3 for the 200A BMS to see all sensors (1 = PCB sensor, 2 and 3 are the external ones)
Fabulous, thank you for the information, I'll still check it though
 
I’m looking for a JBD Smart BMS 4S 12V 200A with Bluetooth and Cold temp sensor. Can someone show me a link to one they have purchased with these features. I can’t seem to find one with cold temperature sensors. Want to makes sure I get the correct one.
Thanks,
Rob
 
I also have one. There is no heater option in the app, at least not on the IOS version.

I did some testing with mine (SP04S03A Partno 16240017), with the heater terminal connected (screw connector), just as the picture from @RV Truck Camper

I have set the charge under temp to 3, release at 5.

For testing, I've connected a 12V 50W H7 halogen bulb between H and battery positive.

With no charge, nothing happens, also not when you reach the set threshold for the low temp disconnect.

When you apply charge, things are differently. With the temp above set under temp, it just charges, nothing special.
If the temperature of ANY of the sensors is below the set temp:
- Charging stops due to low temp
- H connector is switched ON, 12V between H and battery + (thus enabling heater), as long as the 'charge under temp' is not released
- When the temp rises above the set release value (and release delay is expired), heating is disabled and charging restarts. (Charge under temp is released)

Exactly the behaviour you want, there is no need to have the heating running without charge.

Thus: Conditions to enable the heater
- Temp of any of the sensors has to be below set temp (causing a low temp charge disconnect)
- Charge voltage must be applied (otherwise the low temp charge disconnect isn't triggered)
- Charging starts once the release threshold temp is reached, (+ delay value expires) , heater is disconnected

As for the temperature sensors: Mine had 2, and they don't have all to be in low temp: A single sensor detecting too low will work.

Note: I did load the previous settings from my 120A BMS. That one had less temperature sensors, so I had to enable NTC 1/2/3 for the 200A BMS to see all sensors (1 = PCB sensor, 2 and 3 are the external ones)
Thanks DJSmiley, you got there before me and explained so much better than I could.
 
Thanks! I was hoping it was clear, sometimes it's hard to find the proper words/way of expression since English isn't my native language (which is Dutch, and I think google translate is even worse than my crappy English)

I've sold mine, ordered a new one, so can't do more testing untill I receive the new one
 
Thanks! I was hoping it was clear, sometimes it's hard to find the proper words/way of expression since English isn't my native language (which is Dutch, and I think google translate is even worse than my crappy English)

I've sold mine, ordered a new one, so can't do more testing untill I receive the new one
Your English is very good. What charge under temp will you use in reality. Overkill Solar recommend -1c but I was thinking of a little higher as my 15w heaters will take a little time to soak, but don't want the heaters cutting in too often. I also want to add some insulation as my cells just now are almost at the air ambient in my camper which is parked outside...
 
I have set it to 3c.

Keep in mind the sensor is usually not properly measuring the internal cell temperature, but the outside of the case. If I put a cell in the freezer and remove it, a sensor glued to the outside of the cell will reach -1 pretty soon, but I'm quite sure the internals are still way colder.

I did install my temperature sensor beween the cells (used 2mm insulation sheets between the 2 middle cells and made a small cut where the sensor fits), so I think this wil give a more exact reading (less affected by ambient temperature rising)

However, for my van I don't really mind that much about low-temp charging.
When in storage -> Battery is disconnected with approx 60% SOC (Which is best practice for storage), and with the low self-discharge of LFP there is no need to charge.
When in the camper during holiday season: It's not likely to get below 0c outside, let alone inside the van.

I'm not planning to do winter trips, and IF i do... my battery is inside the van. If it gets below freezing INSIDE the van, the battery is not my only concern. Water lines will freeze, stuff will freeze, lot of condensation shit happens, so in the end you WILL keep heating running anyway and keep the inside temp at least 5-10c to prevent those issues.

Also, if you look carefully into the LFP chemistry: 0c is not a hard line... You can charge at lower temps, but only at VERY low currents. And it's also not like -1C: NO charging, battery WILL DIE!!! and +1 Charge at 100A and everything is fine!

Also at +5C, cells don't like high charges, the full charge current can only be done at 15+C or so. For best results your charger should graduately increase charging amps based om temp, but the majority is just on-off.
 
I have set it to 3c.

Keep in mind the sensor is usually not properly measuring the internal cell temperature, but the outside of the case. If I put a cell in the freezer and remove it, a sensor glued to the outside of the cell will reach -1 pretty soon, but I'm quite sure the internals are still way colder.

I did install my temperature sensor beween the cells (used 2mm insulation sheets between the 2 middle cells and made a small cut where the sensor fits), so I think this wil give a more exact reading (less affected by ambient temperature rising)

However, for my van I don't really mind that much about low-temp charging.
When in storage -> Battery is disconnected with approx 60% SOC (Which is best practice for storage), and with the low self-discharge of LFP there is no need to charge.
When in the camper during holiday season: It's not likely to get below 0c outside, let alone inside the van.

I'm not planning to do winter trips, and IF i do... my battery is inside the van. If it gets below freezing INSIDE the van, the battery is not my only concern. Water lines will freeze, stuff will freeze, lot of condensation shit happens, so in the end you WILL keep heating running anyway and keep the inside temp at least 5-10c to prevent those issues.

Also, if you look carefully into the LFP chemistry: 0c is not a hard line... You can charge at lower temps, but only at VERY low currents. And it's also not like -1C: NO charging, battery WILL DIE!!! and +1 Charge at 100A and everything is fine!

Also at +5C, cells don't like high charges, the full charge current can only be done at 15+C or so. For best results your charger should graduately increase charging amps based om temp, but the majority is just on-off.
@DJSmiley thank you for your input, we do intend on using the van this winter if possible (but this will be the first time). I have my temp sensors between the 2 outside cells, which have 6mm poron between them compressed to 3mm. Right now our solar is only managing a few amps although our B2B can go to 60A, not sure what the BMS will do if I start the van at less than 15c? Best get some insulation and the heaters installed ;-).
 
BMS won't limit current. It's just on/off, no current limitation. If the lowtempdisconnect is not active, it just charges whatever you throw at it (assuming the cells aren't full)

I don't know the exact charging curves. Assuming you have 280Ah cells, which can be charged at 1C at normal (20c or so) temperatures, I think it's no problem to charge with 60A at 10c. (60A is only 0.2C). But maybe the manufacturer of the cells can provide a chart with the max allowed charge rates at various temperatures.
Solar provides not so much during wintertime.
Some B2B's do also have a low-output mode which can be selected.

If you can understand German, WCS has some nice video's about their B2B. That one has a variable output current depending on the temperature. It also has a temp sensor on the alternator so the charge current is reduced when the alternator gets too hot.
It's an expensive part, but looks well engineered, and their explanations are great, they apply to LFP in general and not only to their producs.

 
As for the low temp charging: have a look at https://diysolarforum.com/threads/why-you-cannot-charge-lifepo4-below-0-degrees-celsius.2912/

@Dzl placed a screenshot from a Ganfeg datasheet regarding charging at low temps. ( https://diysolarforum.com/threads/w...epo4-below-0-degrees-celsius.2912/post-170940 )
As you can see, 0.2C is the maximum allowed in the 0-7c temperature range. That does match your 60A B2B fine, so no problem probably, assuming your cells are similar (But I think so since they use the same chemistry). On higher SOCs, the 0.2C is reduced to 0.15C, which would be 42A for a 280Ah pack, so some heating might still be recommended. (My B2B is 40A so I'm good, unless the solar does a lot adding up to the 40A from the B2B)

A higher charge at low temps isn't recommended, as you see a higher temperature is required to stay within specs when charging over 0.2C
 
Finally got it all working, it works well although it stops discharging if the charging is disabled. That's a shame really as there's buttons for both in the app
 
I've got two of these on the way as i'll be running 2 x 304AH EVE 12 volt pack setup, so if one fails at least i can get by on one pack until i sort it.

Has anyone pull one of these apart to tap some screw threads in for mounting? i do have some VHB double sided tape in the workshop, but i do prefer a screw mount.

thanks in advance
 
Finally got it all working, it works well although it stops discharging if the charging is disabled. That's a shame really as there's buttons for both in the app
You may need a newer version of the app. I know I had to get a newer version of the PC software to set some of the settings for the 150 amp model.
 
I ordered two of these from this ad/company one week ago on 11/1 and they still haven't shipped them. Is this common? How long did yours take to get?
Thanks
 
I ordered two of these from this ad/company one week ago on 11/1 and they still haven't shipped them. Is this common? How long did yours take to get?
Thanks

Mine took from October 7 to yesterday, November 6th.

I had ordered some previously but paid for faster shipping then, this was the "normal" shipping.
 
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