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Orion Jr.2 BMS thread

My inverter came prewired with 4/0 cable from the + and - bars to the inverter + and - connections. Came with two round magnets to go over each 4/0 cable I believe. I'm guessing they didn't install them because they would bounce around during shipping.

Is one of those ferrites big enough to fit over two 4/0 cables at once?
Or can it only fit over a single cable?

Here's an example of a common-mode choke - two wires wrapped around one ferrite core:


So long as current goes through the two windings in opposite directions, it cancels. Only common-mode noise sees inductance from this choke and is attenuated.
If only one winding is used, or if current is run through the two windings in same direction, at just a few percent of normal current flow the core becomes magnetically saturated, and any further current (e.g. high frequency noise) doesn't increase magnetization so doesn't see any impedance, is not attenuated.

Most vendors didn't publish specs for differential mode use. One did, showing it saturated at a couple percent of what it could carry wired for common mode.
I used a network analyzer to measure a sample of one a colleague was using in a design, and biased the second winding with DC current. I confirmed the very low saturation level.

Go ahead and install them, but if each goes on a single wire I doubt they accomplish anything.
 
Is one of those ferrites big enough to fit over two 4/0 cables at once?
Or can it only fit over a single cable?

Here's an example of a common-mode choke - two wires wrapped around one ferrite core:


So long as current goes through the two windings in opposite directions, it cancels. Only common-mode noise sees inductance from this choke and is attenuated.
If only one winding is used, or if current is run through the two windings in same direction, at just a few percent of normal current flow the core becomes magnetically saturated, and any further current (e.g. high frequency noise) doesn't increase magnetization so doesn't see any impedance, is not attenuated.

Most vendors didn't publish specs for differential mode use. One did, showing it saturated at a couple percent of what it could carry wired for common mode.
I used a network analyzer to measure a sample of one a colleague was using in a design, and biased the second winding with DC current. I confirmed the very low saturation level.

Go ahead and install them, but if each goes on a single wire I doubt they accomplish anything.
Not sure if one will fit over two 4/0 cables but I will find out tomorrow. My inverter manual doesn't mention anything about them. So if one will fit over both + and - wires should I install both in different locations. Say right below the inverter in connections and then closer to the batteries?
 
Both should go close to inverter.
The goal is to reduce high frequency noise as much as possible before it reaches an "antenna", several feet of cable.

If both cables can fit through one ferrite donut, then these will help.
Both cables would go through it in the same direction, from the same side of the ferrite. So one side of ferrite faces the inverter.
That way current flowing to the inverter in one cable and from the inverter in other cable go through the ferrite in opposite directions.

We often wrap a pair of cables through a ferrite several times - effectiveness goes as the square of turns. But 4/0 you're not going to be doing that, just one pass.

Here's a picture of two (split) ferrites around a pair of wires:

 
So if I want to use the multipurpose no. 1 to power the relay I connect multipurpose no. 1 to the positive input of the relay and use the ground wire (white wire no. 6 in manual) to relay ground. Then connect RPO wires to normally open terminals of relay. Does this sound right? My relay experience is limited to installing HID lights on motorcycles and cars/trucks.

Using the multipurpose out allows me to set less conservative low and high cell values as a failsafe?

I had it disconnect the negative of the battery. Make sure your inverter is OK with that. Some want positive disconnected and never negative.

I think it was this: connect relay positive (85) to positive battery. Connect MPO to relay negative (86). Connect 87 to battery negative. Connect 30 to negative bus bar. Test this before connecting the negative bus bar to 30. Make sure the relay clicks ONCE and that you measure voltage between battery positive and relay output (30). This relay makes it complicated so that's why I switched. The description doesn't match the diagram, either :(
 
So I had ordered the Victron Battery Protect 48 before I realized it couldn't be used between the inverter and the battery. I though I would use it to disconnect my 1050W Lester Golf cart charger which I use with my 1600w whisper quiet inverter. No luck. I had assumed since it had the Lion mode for connection to the Victron VE.Bus BMS chare disconnect wire that it would work with either the Multipurpose enable or Multipurpose outputs of the Jr.2

The Victron manuals suck so I'm not sure I can get this working without a relay. Even with a relay it doesn't seem crystal clear how to configure it.
 
l
So I had ordered the Victron Battery Protect 48 before I realized it couldn't be used between the inverter and the battery. I though I would use it to disconnect my 1050W Lester Golf cart charger which I use with my 1600w whisper quiet inverter.

Maybe not a good idea.

 
l


Maybe not a good idea.

This is my charger: Lester Summit II

It certainly wasn't cheap. It has a Lithium setting. Do you think it is a bad idea to use it if I run it through a contractor controlled by my Jr.2 BMS?
 
This is my charger: Lester Summit II

It certainly wasn't cheap. It has a Lithium setting. Do you think it is a bad idea to use it if I run it through a contractor controlled by my Jr.2 BMS?
If it is electronically regulated to a suitable voltage, should be OK. See if settings can be such that BMS never disconnects.
I think the problem Will had was a basic transformer type charger, which had a high open circuit voltage, too much for the electronics of BMS. It probably raised voltage until disconnect happened.

But since electronic chargers have an inductor, I could imagine them making a voltage spike when disconnected. Whether that could damage either charger or BMS I can't say, best to check manual or customer support. If it is a meant for lithium, maybe a BMS with disconnect is assumed. In the link I do see "Lithium-ion BMS communication" which should turn it off rather than causing disconnect.
 
In the link I do see "Lithium-ion BMS communication" which should turn it off rather than causing disconnect.
That never caught my eye. I spoke with them today and they told me there was no way for a BMS to communicate with the charger.
 
That never caught my eye. I spoke with them today and they told me there was no way for a BMS to communicate with the charger.

"Lockout / interlock Single wire Battery temperature Input standard; sensor optional CAN bus communication CANopen ® standard"
 
I just read through the entire thread, very interesting... Hmmmm
I did however notice that not one single person mentioned keeping your DC Wires from Battery to Inverter "together".

A general rule which is often written into Inverter Manuals:
Do NOT keep the battery wires far apart. Keep them taped together to reduce their inductance and induced voltages. This reduces ripple in the battery wires and improves performance and efficiency. (Direct extract from Samlex EVO Inverter Docs and there is a LOT more on this topic in their docs)

I can attest to the amount of "noise" that can ripple through if the wires are NOT together and as I have some pretty long battery cable runs (14') from battery terminal to Inverter) and all of it 4/0 fine strand welding cable (Royal Excelene).

Now I don't use Orion, almost went for it initially but chose to go with Chargery instead which also suffers similar issues with ripple. A lot of BMS' suffer these issues, sadly some mask the issue with reduced sampling or by averaging sampling or other little tricks.
 
I had it disconnect the negative of the battery. Make sure your inverter is OK with that. Some want positive disconnected and never negative.

I think it was this: connect relay positive (85) to positive battery. Connect MPO to relay negative (86). Connect 87 to battery negative. Connect 30 to negative bus bar. Test this before connecting the negative bus bar to 30. Make sure the relay clicks ONCE and that you measure voltage between battery positive and relay output (30). This relay makes it complicated so that's why I switched. The description doesn't match the diagram, either :(
Thanks. My cheap relay arrived today and it works perfectly to put the Schneider equipment into RPO mode. It only draws 1.8 watts (37.5 ma).

48v relay

So these relays can handle 40 amps. That got me to thinking that I can run my 1050 watt golf cart charger (Lester Summit II) through one and use Multipurpose no. 2 to kick it off at the high voltage of my choice. I bought the charger to absorb my Trojan L16s using my 1,600 watt Yamaha clone inverter/generator. Since I already own it might as well wire it up.

Any reason I can't charge through this relay? I'd send my Victron BP48 back and save some $$$
 
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40 A is a bit optimistic with those relays... 30 A would be the max I would pass through that (and even that might be too much).
 
40 A is a bit optimistic with those relays... 30 A would be the max I would pass through that (and even that might be too much).
Thanks. This charger/genset setup puts out just under 20 amps so I'm going to give it a try.
 
Ok, then it should be fine ;)

Put your hand on the relay after some time to be sure it's not getting too hot tho.
 
Automotive size relay, but rated 48V. And 40A (or 20A) is still a pretty good current. What voltage are you using it for?
Switching resistive loads is easier, inductive loads arc more, and higher voltage can sustain an arc easier.

Consider adding a "snubber", a capacitor and resistor in series. Put the snubber across the contacts.
When contacts open, current flows momentarily into the capacitor, allowing contacts to get far enough apart to avoid arcing.
I've done that with just a capacitor, but capacitor discharges into the contacts when they close, causing some burning.
Resistor limits current flow to V/R.
(Another snubber design has diode in parallel with resistor, so upon opening capacitor charges instantly, but on closing it discharges slowly through resistor.)
 
Did you manage to get your video uploaded? Could you post a link please?

I did ... it's unlisted and I only sent it to hammick in a PM. I'll review it and see if it's appropriate to be public. I do intend a NEW Orion BMS video at some point that will be public.
 
I did ... it's unlisted and I only sent it to hammick in a PM. I'll review it and see if it's appropriate to be public. I do intend a NEW Orion BMS video at some point that will be public.
OIC, okay thanks. I have similar issues/questions as Hammick so was wondering if I could glean a little more insight from the vid.
 
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