Will blasts Chargery

[Bob B]

When I worked in the control industry, we would put a sniffer on the competitions comm line and then build a driver into our equipment to simulate their stuff .... it was legit as long as you discovered their communications that way.
I REALLY used to hate those kind of integrations .... but they worked.

Yes I have ... but the controllers I used also had the ability to do text programming as in "If Then Else" and other macro statements that were very powerful. The 2 tools could be used in combination ... and the each had a place.

 

[Bob B]

The problem with most of these standards is that they also allow a Mfg to use proprietary elements within the standard protocol .... and the various manufacturers will use it heavily. The Mfg really don't want a truly standard protocol.
Lon and Bacnet ... and sometimes Modbus were some of the "standard" protocols we adhered to and integrated with .... so the spec would be written that everything had to adhere to one of those protocols ..... then the integration nightmare ensued.

 

[KohalaJim]

Yes I have ... but the controllers I used also had the ability to do text programming as in "If Then Else" and other macro statements that were very powerful. The 2 tools could be used in combination ... and the each had a place.

"Structured Text" often fuses with ladder and function blocks in the PLC realm... my last brush was with B&R and Automation Studio.

 

[Bob B]

"Structured Text" often fuses with ladder and function blocks in the PLC realm... my last brush was with B&R and Automation Studio.

Yes ... one of the PLC's I worked with had those capabilities ..... Some of the controllers of "ours" had similar capabilities for using text somwhat like Pascal and also integrating logic tables.

 

[cass3825]

Yes ... one of the PLC's I worked with had those capabilities ..... Some of the controllers of "ours" had similar capabilities for using text somwhat like Pascal and also integrating logic tables.

IEC 61131-3 has made an effort to “standardize” languages mentioned in this thread. As you mentioned, each manufacturer tweaks it just enough to complicate integration. As a controls engineer, it keeps things interesting!

IEC 61131-3 - Wikipedia

en.m.wikipedia.org

 

[JoeHam]

IEC 61131-3 has made an effort to “standardize” languages mentioned in this thread. As you mentioned, each manufacturer tweaks it just enough to complicate integration. As a controls engineer, it keeps things interesting!

IEC 61131-3 - Wikipedia

en.m.wikipedia.org

That’s the nice thing about standards.

There’s so many to choose from! ?

 

[KohalaJim]

To ensure I am following, is the use case for a Bi-Di SSR to isolate the battery pack via a "Di" directional LVD event, and enable normal "Bi-Di" for charge/discharge?

Thanks in advance for clarifiying...

Sorry to double post, but can one of the knowledgeable solar pros in this thread address this Q? It got buried in a posting flurry and I was hoping I could get a confirmation on the use case/cases. Still trying to learn in this realm.

 

[cass3825]

Sorry to double post, but can one of the knowledgeable solar pros in this thread address this Q? It got buried in a posting flurry and I was hoping I could get a confirmation on the use case/cases. Still trying to learn in this realm.

I don’t believe so. A “bi-di” SSR acts just like a set of regular relay contacts, passing current in either direction whenever the “coil” is energized, and blocking current in either direction when it is not energized.

 

[KohalaJim]

I don’t believe so. A “bi-di” SSR acts just like a set of regular relay contacts, passing current in either direction whenever the “coil” is energized, and blocking current in either direction when it is not energized.

Thanks, if that's what it means, then the "di" inference is a misnomer (in my interpretation).
no_flow != directional_flow in my mind, but YMMV.

 

[bostonbuzz]

Chargery website is down
Trying to figure out why my balancing is so slow. 280ah 4s1p pack. Trying to top balance the hard way, letting one cell max out and cut off charging then balance with chargery before charging again. 8mv max accuracy is hurting.
Anyone have a 8T manual?

 

[Craig]

Chargery website is down
Trying to figure out why my balancing is so slow. 280ah 4s1p pack. Trying to top balance the hard way, letting one cell max out and cut off charging then balance with chargery before charging again. 8mv max accuracy is hurting.
Anyone have a 8T manual?

How far off are the cells and what time frame do you consider slow?

 

[bostonbuzz]

.025 difference left overnight to balance to 8mv, still .02 difference.

8mv balancing accuracy is the max, I’m running v1.2 software, is the update better on balancing?

If the website doesn’t go back up can we put the software and manuals in the resources section?

 

[Craig]

8 mv is pretty close I usually get mine to about 35mv and call that good I have never been closer than 16Mv

What did you set the balance differential to?

I will see if I can get the manual up for you

 

[Craig]

http://www.chargery.com/doc/Chargery_BMS8T_specification_V3.0.pdf

 

[bostonbuzz]

Thank you. I set it to 8mv.
This gets back to wills criticism on the cell voltage difference parameter. I thought that 30mv was way too big, so I kept it there. Reading this, I put it to .5v. If one cell is over or under the BMS will cutoff, so no need for a cell differential cutoff. I guess I can live with 20mv difference, although I read elsewhere you should get closer. Thoughts?
I also still don’t know what some parameters do. Temperature difference? State of Charge meter %?

 

[Craig]

State if charge meter will cut out at wherever % that is set for same thing as LVD but by other method. Temp difference will cut off if the difference in temp between the 2 probes is greater than the setting.

I would set differential cut off to 300 mv and the balance parameter to 8mv to let it keep things as close as possible. But allow some leeway.

 

[Ampster]

I thought that 30mv was way too big, so I kept it there. Reading this, I put it to .5v. If one cell is over or under the BMS will cutoff, so no need for a cell differential cutoff.

Unless my decimal math is off 30mv is 0.03v which is 1% on a 3.0 v cell. Were you referring to the accuracy of the BMS or the value of the setting?

 

[Airtime]

I'm a little late to this thread but I'll chime in on the Chargery BMS. I bought a BMS8T a month ago based on reviews from multiple people on this forum. Just now turning it on--don't have my cells yet so just trying out the current meter and shunt with an old lead acid battery.

First--I don't get why Will had such a hard time calibrating his shunt. I wanted to use the Victron BMV-712 shunt rather than the cheap Chargery shunt. Took me all of 10 minutes, I didn't notice any tricky button timing issues, and it worked first try. Programming a watch is harder.

But the current read-out only had 1A resolution vs. 0.1A showing in the manual, not yet sure why that is. And the other weird thing was the current reading with the inverter running. I had an inverter driving a 300W lamp in the system, pulling about 22A. The Victron BMV-12 had a nice steady 22A reading. But the Chargery would cycle from 17A up to 27A and back, with a period of about 7 seconds. So I put my clamp current meter on the inverter input, and read 22A DC but also saw about 7A AC.

I don't have a scope so I have no idea what the frequency of the inverter current ripple is. I've not played with inverters before, I didn't realized they would have so much current ripple. The Chargery 7 second cycle is probably aliasing from the Chargery sample rate beating against whatever the inverter ripple frequency is, with no averaging in the Chargery. It makes the current readout useless with my inverter. I'll have to get a cheap scope so at least I can see the waveform and understand what's going on.

Just to check whether there was any issue running direct from the battery under 15V, I tried powering the Chargery from an external 15V supply but it acted the same.

 

[Craig]

I think the ripple thing goes back to the Chargery originally being for EV with no inverter. Obviously this makes reading hard but it is also probably more accurate.

Why is current reading useless? If it is showing actual current. Not trying to argue just want to know people's thoughts.

 

[Ampster]

I think the ripple thing goes back to the Chargery originally being for EV with no inverter. Obviously this makes reading hard but it is also probably more accurate.

Most EV conversions run at a lot more Amps than the Chargery can handle. There are a lot of EV conversions out there with 3 phase motors. The motor controller is a 3 phase inverter, and they can be noisy. But many of those run at voltages in excess of 48 volts. But most smaller golf carts use DC motors.