2x Chargery 16T's, 1x DCC ?

Bob B

Photon Sorcerer
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Sep 21, 2019
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On another thread, I suggested to @Chargery that they do the common / separate port logic in the BMS rather than having the confusion of special cables and different models of the DCC.

If a parameter was added to select whether or not the BMS would act as common port or separate port, it would just be a matter of programming to determine whether the charge and load outputs act together or independently.
That way there would be no need for special cables or different model DCC's.

I didn't get a response to that suggestion .... so probably not on their radar to do it that way.
 

Factory400

Solar Addict
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Jul 15, 2020
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If you use an AND configuration for the control - this could work.

Essentially that means if BMS1 AND BMS2 are sending a 12v signal to the DCC - it would turn on. If either of the BMS unit commanded the DCC to turn off - it would turn off the whole system. This could be done with a few small signal relays and some other simple parts.

Seems reasonable enough to me.
 

Chargery

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Apr 22, 2020
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yes, Two charge control signal from two BMS must be "AND", Two discharge control signal from two BMS must be "AND", then control one DCC, not only need "AND" charge or discharge signal, but also need 12V VCC drive DCC or RELAY.
with this configuration, when one cell of 32 cells volage reach HVD setting, DCC open and cut off charging. when one cell of 32 cells volage reach LVD setting, DCC open and cut off discharging.

as far as my understanding, if two 16S packs paralleled, one battery pack should be as back up. when one pack cut off discharge, another pack need continue to discharge, so the configuration is not suitable.

if the purpose of two packs paralleled is to extend discharge time or increase maximum discharge current, it is better to parallel two cells, then connect 16 two cells in series. one BMS and one DCC is enough.
 

Chargery

Solar Addict
Joined
Apr 22, 2020
Messages
105
On another thread, I suggested to @Chargery that they do the common / separate port logic in the BMS rather than having the confusion of special cables and different models of the DCC.

If a parameter was added to select whether or not the BMS would act as common port or separate port, it would just be a matter of programming to determine whether the charge and load outputs act together or independently.
That way there would be no need for special cables or different model DCC's.

I didn't get a response to that suggestion .... so probably not on their radar to do it that way.
BMS control charge and discharge separately, on BMS, cannot identify the charge and discharge is on common port or seprate port. on both port, two control signal is total same. common port or separte port depend on user's choice and design, only DCC is different used on common port or separate port, if DCC is unidirection, only receive charge or discharge control signal, that is no problem, but our DCC is bi-direction, it can receive charge and discharge signals, when used on common port, it is easy and connect DCC to BMS directly by our cable. when used on seperate port, either for charge or for discharge, the DCC only need receive one control signal, connct two DCCs to one BMS by our another cable. so the DCC need idenfty common port ( two control signal) or seperate port (only one control signal.
 

Bob B

Photon Sorcerer
Joined
Sep 21, 2019
Messages
3,809
BMS control charge and discharge separately, on BMS, cannot identify the charge and discharge is on common port or seprate port. on both port, two control signal is total same. common port or separte port depend on user's choice and design, only DCC is different used on common port or separate port, if DCC is unidirection, only receive charge or discharge control signal, that is no problem, but our DCC is bi-direction, it can receive charge and discharge signals, when used on common port, it is easy and connect DCC to BMS directly by our cable. when used on seperate port, either for charge or for discharge, the DCC only need receive one control signal, connct two DCCs to one BMS by our another cable. so the DCC need idenfty common port ( two control signal) or seperate port (only one control signal.

If all DCC's only needed 1 input, and a user selectable parameter was added to select common vs independent in the BMS, there would be no need for different hardware connections.
 

Capt Bill

Sailing Options
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Mar 18, 2020
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Redwood Valley, Cailfornia/ Montezuma, Costa Rica
Hi all,
First time poster, and I've got to say how happy I'am to have come across this group, the knowledge here is unmatched anywhere on the www!!
Anyway, apologies if this has already been covered, i did some searching and could find anything, and apologies for the crude drawing, however i think it covers what im asking.
The build is 32x 3.2 cells, i have the option of 2 cells in parallel and 16 of those pairs in series, or, 16 cells in series with two of those stings paralleled (this is preferred by me), BMS is a Chargery 16T with a 600A DCC.
Question is can i run two 16T's on the two strings, have each 16T drive an interposing relay (R1 & R2) contacts of which will series up to drive the 600A DCC (power through the contacts to the DCC 'coil' can come from either 16T#1 or #2). Each string will have its own shunt which parallel together downstream at the DCC.
I'am aware that i lose any sort of redundancy doing it this way, but is it possible while maintaining adequate protection on both strings ?View attachment 29696
I am considering options for combining 2 x 24v or 48v 280 Ah battery banks together, using two 300A Chargery BMSs ... , and could share this idea for your 48v set up as an option (no good enough drawing yet). Use the double input DDC to cut off your battery (for BMSs' discharge triggers only) via connecting one DDC input to discharge trigger of one BMS, and the other DDC input to the the discharge trigger of the other BMS. That would cut off your full battery (as shown in your diagram) when one or the other BMS detects a cell low voltage, or over amp draw, or way low temp, via releasing the 12v to zero @ a BMS Discharge trigger event. ... Then to deal with the BMSs' Charge side triggers ... Consider cutting OFF your Solar In (and possible Grid IN too) via 2 SSRs + mechanical relay options via the BMS 12v charge side triggers. Lots of options ... Here is one: ... One could put two SSRs (Solid State Relays) side by side, with each of the SSRs input terminals (usually rated for 3-32vdc ... for switching LOAD ON) connected to each BMS's charge side triggers (as in ... one BMS to one SSR, the other BMS to the other SRR) ... and ... then Run your fused battery 24v or 48v power to your Solar In Control Relay through the load side of those 2 side by side SSRs in Series ... to control your Solar In. Find a relay with a 48v coil that is properly rated for DC current (or use a 24v coil relay matched a low idle draw type voltage reducer piece), and run fused 24v or 48v current through your two SSRs load terminals in series to a Solar In Relay. ... Then Losing the 12v BMS charge side current from either BMS would cut OFF your Solar IN. ... . You (&/or I) could figure out a way to AC current IN ... If cutting your grid charger or auto auto generator charger might be a factor for protecting your battery. I note: SSRs take running the current in proper polarity direction to work. ... Here's an good looking mechanic relay option I recent acquired (to test): w a 24v coil /80A DC rating, that can handle two separate Solar IN Circuits ( only $23 /will see if adequate:

... I think that would work good. I can also think of an option to cut off one 48v battery bank or the the other separately (on the discharge side triggers) via throwing in a second DDC contactor or an appropiately rated relay on the battery circuit (one on each 48v Battery bank). Food for Thoughts and Options ... maybe a diagram later :+)
 
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