PowerFlex 70 Parameter 161 vs 162 Bus Reg Mode

[Chipper]

PowerFlex 70 drive parameters 161 and 162 are Bus Reg Mode A and Bus Reg Mode B, respectively. What is the purpose of Bus Reg B and how does it compare/contrast to Bus Reg A? Thanks in advance for your insight!

 

[jraef]

No difference. You have 5 choices (counting "Disable") for how you want the DC Bus Regulation to function. If you have two different scenarios where you might want it to function differently, you can program a Digital Input to select Bus Reg B, which will override your programming of Bus Reg A for as long as that DI is High. So for example if you normally want the DC bus regulation to drop the frequency as it's method of regulating, you set bus Reg A to "1". But if, on some circumstances, you do NOT want that to happen, i.e. speed accuracy is critical, then you selecting Bus Reg B via a Digital Input to either Disable it (setting "0") or if you have a DB resistor installed, use Dynamic Braking (setting "2").