Chargery BMS, DCC (Solid State Contactor) thread.

[tim0shel]

when DCC cut off charge or discharge, the voltage drop from input and output is caused by internal surge suppressing circuit, means mosfet is turned off, although the voltage is 12.82v on output, but the battery don't be charged or discharged. when the STATUS LED on, means mosfet is turned on, the voltage on input and output has not difference, battery can be charged or discharged.

when internal temperature over 41 C, the fan will turn on, and powered by battery, the fan current is around 0.2A at 12V. when udner 38C, the fan will turned off.

You're correct here the mosfet is turned off as the DCC300 is not coming on hence why the other light does not light up. Status light when flipping the switch comes of for less than a second and goes back off. Reason I though it was working was due to the load side working like some USB ports I was using. But this is Back Flowing from the DCC100.

Also the fan constantly runs, it does not shut off and the temp recently has been almost 63 F or 17.2 C .

 

[Chargery]

Jason,
Thank you so much for this detail. Understand you are busy and think you all had a Holiday. Should be good reference for someone else in future. I do have BMS8T and 4S battery, I did change the wiring after I was looking through some photos etc. I did change it for discharge on the DCC 300 and Charge on the DCC 100 as it was designed to be. This will only allow it to turn correct one on and off. But seems my problem has been the DCC300 will not come on. All power is back flowing through the charge DCC100.

When DCC-300 will not come on, the status on DCC-300 is off, means the BMS cut off the discharge, you can see the discharge LED on ISO board is off, correct? so please see the BMS LCD, confirm which warning events are trigger, the triggered setting is showed in RED text, such as cell voltage difference, SOC, or others. by the way, the DCC is mounted between battery positive and load positive, DCC-100 is mounted between battery positive and charger positive, please check it. final thing is both DCC must be pasted "SEPARATE PORT" lable.

 

[tim0shel]

When DCC-300 will not come on, the status on DCC-300 is off, means the BMS cut off the discharge, you can see the discharge LED on ISO board is off, correct? so please see the BMS LCD, confirm which warning events are trigger, the triggered setting is showed in RED text, such as cell voltage difference, SOC, or others. by the way, the DCC is mounted between battery positive and load positive, DCC-100 is mounted between battery positive and charger positive, please check it. final thing is both DCC must be pasted "SEPARATE PORT" lable.

@Chargery I verified the light, or both lights are on the ISO board this was my reason for the voltage drop (Mosfets off) and confirmed from you the status light indicates when it is on. All settings have been validated many times and no warnings.

Your last statement goes to one of my original questions that I have asked many times over periods of times when I hear about these DCC's and used in separate port. I purchased this DCC-300 from you in the beginning around July 2020 which I just have gotten around to building this project and getting everything hooked up (It does NOT have label on it pasted as Separate port) no mention on common or separate during this time. But when this was being mentioned later on is why I questioned the one I had. If this one is not compatible to run in separate port I'm in a mess!

Wiring is correct I've had many times to go over it and over it since I started this project and started building it. I have posted a diagram in a previous post.

 

[Johannlog]

I have my Chargery BMS8T 300A. DC Contactor 300A. For my 2p8s 24V battery build. However the BMS came with no instructions. And I've never connected one before.
Anyone have a link to something that could help me know how to wire this up?

 

[Steve_S]

DOCS are HERE: http://chargery.com/BMS8T.asp
Firmware updates etc here: http://chargery.com/update.asp

 

[Johannlog]

DOCS are HERE: http://chargery.com/BMS8T.asp
Firmware updates etc here: http://chargery.com/update.asp

Thanks. It looks like they didn't send me a power supply, is that what goes to this DC barrel receptacle?

 

[Steve_S]

The BMS powers itself from either the battery harness or from an external source. Using an external source, even the battery itself from the terminals, helps reduce flutter.

 

[MrPhoton]

Testing the DCC to ensure it is OK the resistance between two terminals, should be 7.5K ohm, meaning the DCC is ok, you can power it.
DCC Installed on the Negative Side will shutoff fully.
DCC installed on the Positive positive side (with ISO Board in place ONLY) will not completely cutoff and provide low amp voltage. which is supposed to serve Precharge needs.

Per Jason, Nov.2020.

I asked Jason about the DCC-300 v1.1 instructions (DCC on POS) vs. the v1.0 DCC (and BMS8/16T) instructions which all show DCC on NEG.

He said that some customers have "suggested" that DCC on POS is safer.

At the risk of finding myself quick schooled by the EE community and Mike Holt viewership (he's awesome)--- would be great to hear a learned view on the dangers of NEG DCC vs. POS DCC in context of a separately derived systems for ESS.

Thank you.

 

[Johannlog]

I asked Jason about the DCC-300 v1.1 instructions (DCC on POS) vs. the v1.0 DCC (and BMS8/16T) instructions which all show DCC on NEG.

He said that some customers have "suggested" that DCC on POS is safer.

At the risk of finding myself quick schooled by the EE community and Mike Holt viewership (he's awesome)--- would be great to hear a learned view on the dangers of NEG DCC vs. POS DCC in context of a separately derived systems for ESS.

Thank you.

I was going to try connecting it to the Positive but since I don't entirely know what I'm doing maybe I should go with putting the DCC on the Negative side?
I do have the ISO board but don't know exactly what it does.

 

[Johannlog]

The cable that runs from the BMS to the battery terminals is 24 AWG.
How do I connect it to the battery terminals?
I don't want to use ring terminals, as I haven't found any around here that small, and even if I did I don't have a crimper that goes that small....

 

[Made in North Pole]

@Chargery I'm wondering if the common port DCC would work as a separate port device if the signal is wired in parallel to both inputs .... For instance, if the 12V charge enable power were split and tied to both inputs on the DCC.

Did you get an answer to this? Thinking of doing the same.

 

[tim0shel]

The cable that runs from the BMS to the battery terminals is 24 AWG.
How do I connect it to the battery terminals?
I don't want to use ring terminals, as I haven't found any around here that small, and even if I did I don't have a crimper that goes that small....

If at all possible solder some ring terminals on there. Really nothing else I would suggest actually and don't get too impatient and regret it later. If anything Amazon if you have prime will get some items to you in a decent time.

 

[tim0shel]

Did you get an answer to this? Thinking of doing the same.

I would like to know the same and if know one does know I think I have a good test piece I could try it on. But everything is going through the ISO board so not sure if this throws a curve ball at it as well?

 

[Johannlog]

I've connected the BMS and DCC.
Attached are some images of the display... Not sure what is going on here, but it saying some cells are at 00.0v etc even tho they aren't. (I've topbalanced)
Checked the connections and they seem to be good, what else could be going on?
(2p8s 24v)

 

[BiduleOhm]

Pretty sure you've swapped two wires (6 and 7) but it's hard to tell for sure from the picture.

 

[Johannlog]

Pretty sure you've swapped two wires (6 and 7) but it's hard to tell for sure from the picture.

That's it. I had several swapped. Thank you.

Do I connect the battery terminal to the "A" or "B" of the DCC

Also didn't ready any specific instructions on this in the documents

 

[Bob B]

Did you get an answer to this? Thinking of doing the same.

No I didn't .... I'm not using the DCC or I would test it. Might be worth emailing that question to Jason.

 

[MisterSandals]

I read this entire thread a couple weeks ago and my impression was that a newer version was in the works that addressed the closeness of the DCC’s terminals.
Is the DCC v1.1 the new version with terminals still precariously close?



I grabbed this from a few posts prior to this. Geesh, even with the red plastic piece wedged in there, it’s mighty close! I am ready to buy a couple of DCCs but cannot bring myself to accept this.

And what is the result of these touching (w/300A)? Does it just disable the cutoff functionality with a short (bad for battery protection) or does it damage the DCC (too)?

 

[Johannlog]

I read this entire thread a couple weeks ago and my impression was that a newer version was in the works that addressed the closeness of the DCC’s terminals.
Is the DCC v1.1 the new version with terminals still precariously close?

View attachment 70174

I grabbed this from a few posts prior to this. Geesh, even with the red plastic piece wedged in there, it’s mighty close! I am ready to buy a couple of DCCs but cannot bring myself to accept this.

And what is the result of these touching (w/300A)? Does it just disable the cutoff functionality with a short (bad for battery protection) or does it damage the DCC (too)?

I found it uncomfortably close, I just purchased it about 4 months ago.
The plastic is actually the cover on the MRFB 300A fuse terminal.
Still trying to figure out which side of the DCC should be on the battery terminal.

 

[MisterSandals]

Still trying to figure out which side of the DCC should be on the battery terminal.

Looks like the terminal on the right in this chargery pic…

My “guess” would have been that it does not matter but following the official pic should be safe(st).