Balancing Single Phase Transformers on Three Phase Panel Revit 2021 Bug

[Anonymous]

I have a 277/480V 3Φ distribution panel. This feeds (4) 480V 1Φ to 120/240V 1Φ transformers. Each transformer has its own 120/240V 1Φ panel. When I'm in the main distribution panel schedule I try to move the loads to balance and the loads are only on the A & C phase. Any time I move a transformer to phase B it shows zero load. The secondary side panels are only loaded on phases A & C but there is no way to change them. They should just look at whatever phase the transformer is on which is what MEP 2020 does.

[gmaldoon]

I have the same problem 

[sragan]

Is the panel feeding the transformers a "panel" or is it a "switchboard"?  If its a switchboard, you might have to change it to a panel.   

If that's not the problem, make sure the connectors for the transformers have 2 poles and are set for "balanced" loads.

[Anonymous]

The family is a panel and the transformer is 2 pole and balanced. The issue is when powering a 480 to 240 single phase transformer from a 3 phase 480v panel. What happens is that when the tx is powered the secondary of the transformer is locked to phase AC but panel schedule shows only AB so the B phase load is empty in the panel schedule. This is unique to Revit 2021. I used the same families and methods in previous versions and never had this issue.

[Anonymous]

I found a very clunky work around.

1. Remove secondary panel from transformer.

2. Copy panel.

3. Power copied panel to transformer.

4. Power original panel to transformer.

5. Remove copied panel from transformer.

You should now be able to see the correct loads in the panel schedule. Crazy work around but it works for me.

[sragan]

I tried it in 2021, and didn't have any issues with using a single phase transformer.

The loads divided up as expected.

[Anonymous]

Is it balanced on the primary side. I misspoke earlier. That is where the issue is. See the attached clip of what I did. I had two 120V loads powered to P240. Then powered P240 to TX and TX to P480. I moved the 120V loads to phase A and phase C.  Also, A&C is what the 240v panel defaults to.  On the 480V panel, the only way to get the loads to show correctly is to have the TX on phases AC. If it is on B, the schedule shows zero load.

[gmaldoon]

Thank you I will try that.