Stacked Rosie Stress Test / 13859W

[wsaharem]

I'm not sure this is a "real" stress test because I didn't break it, but wanted to share my results from my stress teset today. I was impressed with Rosie.

Load:
13859W on AC, 12370 on Battery (something finished or turned off)

Things providing the load.
2 4gal bosch water heaters (1440W each)
1 5 ton air conditioner (observed 3000W)
1 20 btu mini split (observed 1920W)
1 Fortress 1.6 HP air compressor (1000W observed)
1 Metabo .15 HP air compressor
2 1500W space heaters on high heat
1 heat gun on high
Microwave
Lots of lights and house fans (most of my lights are led)
3 ceiling fans
Stove vent fan on high speed

The highest load I noticed on the MNGP2 was 13859W. Well within 2 Rosies.
At 13895W, that's 57A, so close to the 1 breaker that is served from a stacked set of Rosies (which is too small in my mind)
Max battery consumption 255a (across both Rosies)
2 alarms. 2 L2 OverCurrent error on both Rosies and Grid Disconnect Warning.
Zero issues switching from AC to Battery and Back (a couple of times). Maybe some slight led flickering in my garage lights.

 

[seneysolar]

This is from the midnite site, sounds like those can take a beating.

 

[koppted]

I'm not sure this is a "real" stress test because I didn't break it, but wanted to share my results from my stress teset today. I was impressed with Rosie.

Load:
13859W on AC, 12370 on Battery (something finished or turned off)

Things providing the load.
2 4gal bosch water heaters (1440W each)
1 5 ton air conditioner (observed 3000W)
1 20 btu mini split (observed 1920W)
1 Fortress 1.6 HP air compressor (1000W observed)
1 Metabo .15 HP air compressor
2 1500W space heaters on high heat
1 heat gun on high
Microwave
Lots of lights and house fans (most of my lights are led)
3 ceiling fans
Stove vent fan on high speed

The highest load I noticed on the MNGP2 was 13859W. Well within 2 Rosies.
At 13895W, that's 57A, so close to the 1 breaker that is served from a stacked set of Rosies (which is too small in my mind)
Max battery consumption 255a (across both Rosies)
2 alarms. 2 L2 OverCurrent error on both Rosies and Grid Disconnect Warning.
Zero issues switching from AC to Battery and Back (a couple of times). Maybe some slight led flickering in my garage lights.

Can you tell me which one of the CAN connections do I connect the MNGP2 to? One says CAN IN, the other says CAN OUT. There is a placeholder rj45 plug on one of the CAN connections on both the MNGP2 and the Rosie, question is which connections to which. It doesn't say in the manual.

 

[wsaharem]

Can you tell me which one of the CAN connections do I connect the MNGP2 to? One says CAN IN, the other says CAN OUT. There is a placeholder rj45 plug on one of the CAN connections on both the MNGP2 and the Rosie, question is which connections to which. It doesn't say in the manual.

My MGNP2 is connected to the CAN IN on the Rosie. It should be a “bus” and “shouldn’t” matter, but my stacking only works one way. In to out etc. The manual has a lot to be desired and is way out of date. If I got this wrong, just reverse it. Out to In etc.

 

[wsaharem]

This is from the midnite site, sounds like those can take a beating.
View attachment 218756

Yep! I’m still playing with it to understand it better and understand it’s idiosyncrasies, but so far pretty happy. I still want to come up with a consistent load (the heaters stopped running when the room got hot enough), and I need to get a better feel for the bulk charge mode. It slams the batteries when AC is turned back on and I felt the negative cable get a little warm at the shunt.

 

[Brucey]

I'm not sure this is a "real" stress test because I didn't break it, but wanted to share my results from my stress teset today. I was impressed with Rosie.

Load:
13859W on AC, 12370 on Battery (something finished or turned off)

Things providing the load.
2 4gal bosch water heaters (1440W each)
1 5 ton air conditioner (observed 3000W)
1 20 btu mini split (observed 1920W)
1 Fortress 1.6 HP air compressor (1000W observed)
1 Metabo .15 HP air compressor
2 1500W space heaters on high heat
1 heat gun on high
Microwave
Lots of lights and house fans (most of my lights are led)
3 ceiling fans
Stove vent fan on high speed

The highest load I noticed on the MNGP2 was 13859W. Well within 2 Rosies.
At 13895W, that's 57A, so close to the 1 breaker that is served from a stacked set of Rosies (which is too small in my mind)
Max battery consumption 255a (across both Rosies)
2 alarms. 2 L2 OverCurrent error on both Rosies and Grid Disconnect Warning.
Zero issues switching from AC to Battery and Back (a couple of times). Maybe some slight led flickering in my garage lights.

It looks like the positive from lynx to the rightmost Rosie is a fair bit longer than the one going to the left most Rosie? I know with Victrons positive cables have to be the same length when running in parallel (and same for negatives), maybe that doesn't apply for the Rosies?

 

[Brucey]

This is from the midnite site, sounds like those can take a beating.
View attachment 218756

So that's interesting from a high availability perspective, if the master can keep going even if the slave fails. I guess equal chance of a master failing.

Whereas a Victron pair will shutdown and need to be reconfigured to run as a single unit.

 

[seneysolar]

So that's interesting from a high availability perspective, if the master can keep going even if the slave fails. I guess equal chance of a master failing.

Whereas a Victron pair will shutdown and need to be reconfigured to run as a single unit.

I hadn't thought about that, good point.

 

[seneysolar]

Yep! I’m still playing with it to understand it better and understand it’s idiosyncrasies, but so far pretty happy. I still want to come up with a consistent load (the heaters stopped running when the room got hot enough), and I need to get a better feel for the bulk charge mode. It slams the batteries when AC is turned back on and I felt the negative cable get a little warm at the shunt.

What is your max AC charge rate set to?

 

[wsaharem]

What is your max AC charge rate set to?

15 amps.

 

[wsaharem]

So that's interesting from a high availability perspective, if the master can keep going even if the slave fails. I guess equal chance of a master failing.

Whereas a Victron pair will shutdown and need to be reconfigured to run as a single unit.

But, if the master fails, they both fail. You would need to reconfigure and depending upon your wiring and breaker configuration, you might have to do some minor reworking to have the slave become a stand alone master.

 

[wsaharem]

It looks like the positive from lynx to the rightmost Rosie is a fair bit longer than the one going to the left most Rosie? I know with Victrons positive cables have to be the same length when running in parallel (and same for negatives), maybe that doesn't apply for the Rosies?

Support said I would experience a slight voltage difference, but would not be overly impactful. I’m running both in parallel right now and I see draw from both Rosie’s just fine.

 

[seneysolar]

15 amps.

What do you mean by "slams the batteries "? 15A is not much.

I can see the draw from the batteries 200+A making the cables warm while inverting, but not charging at 15A.

You may want to play with a DC clamp meter to verify whats going on and in what direction.

 

[wsaharem]

What do you mean by "slams the batteries "? 15A is not much.

I can see the draw from the batteries 200+A making the cables warm while inverting, but not charging at 15A.

You may want to play with a DC clamp meter to verify whats going on and in what direction.

Slamming batteries means I’m seeing 100+ amps at the battery side (which should be ok since they should be able to handle 200 amps). Maybe I had it at 20amps before which would equal 100A on the 48V battery side. Will definitely be doing more tests with the amp meter and my infrared scanner. All battery cabling is 4/0 and have 300A breaker at the inverter, 400a mega at the busbar and 300A for Class T at the batteries, so I should be ok, but want to really stress it on the recharging process. My only concern was the warming of some of the cables, but not sure what normal should be when the cables are handling 100-200amps?