Regenarative mode: It trips to F2 when stopping.

Hi,

Found a topic regarding similar problems. I have a the application where V20 runs a motor of the hammer. Motor is attached over the belt with driving wheel of the hammer.

I have a problem with regenarative mode. It trips to F2 when stopping.

I have extend the ramp-down time and then there is no F2 fault.

But the application demands shorter ramp-down time so I decided to order breaking module and breaking resistor.

I configured it via Sinamics configurator for my V20 2,2 kW - 6SL3210-5BE22-2UV0

• 6SL3201-2AD20-8VA0
• 6SL3201-0BE21-0AA0

I looked the Sinamics V20 manual regarding  wiring and that is clear.

You suggested to disable V_dc_max controller ? Is that ok? 

Is there any other parameter to be changed expect ramp-down time which should be reduced?

What is the recommendation for adjusting Duty cycle control knob on breaking module?

• 5: 5% duty cycle
• 10: 10% duty cycle
• 20: 20% duty cycle
• 50: 50% duty cycle
• 100: 100% duty cycle

https://cache.industry.siemens.com/dl/files/866/109773866/att_1007343/v1/V20_dynamic_braking_prod_info_1019.pdf

Technology Team

Hi,

as Piscean wrote, increasing the ramp down time is one solution.
Another would be activating the V_dc_max controller, which expands the ramp down time depending on the DC link voltage.

The best solution would be a brake unit with 6SL3201-2AD20-8VA0 an attached resistor hence the V_dc_max controller needs to be disabled

Please find section B1.3 and 1.4 in the V20s manual for selection, connecting and commissioning

------------------------------------------------------------------------------------------
Split from V20_Drive Breaking resistor.

How often will the braking resistor have to absorb energy from the motor?

It sounds like every time the hammer operates.  How fast does the hammer need slowing down (drive absorbing energy)?

You can get pretty complicated with braking resistor configurations if needed for your application.

The end result is the braking resistance needs to be within the tolerance for the proper DC braking resistor for your drive.  However, there is no rule stating only a single resistor can be used.

For example, if you need 30 Ω, but you need to a faster fault-free ramp down, you need more power absorption from the same 30 Ω.  If a single 30Ω resistor can absorb 925W, if you use 4x 30Ω resistors in a series parallel configuration, theoretically, it can absorb 4x the energy.

Total resistance is 15+15=30Ω but total absorption capacity is theoretical 4x925W = 3700W.

At some point, you are limited by the components and wiring of the DC bus.

DC Brake manufacturers can create a custom brake that works like this provided the drive can support it.  For high speed manufacturing, these types of things generally have a very fast return on investment.

          30Ω            30Ω
      ,--/\/\---,     ,--/\/\---,
o-----    30Ω   ------   30Ω    ------o
      `--/\/\---'     `--/\/\---'

gigx205

Hi,

Found a topic regarding similar problems. I have a the application where V20 runs a motor of the hammer. Motor is attached over the belt with driving wheel of the hammer.

I have a problem with regenarative mode. It trips to F2 when stopping.

I have extend the ramp-down time and then there is no F2 fault.

But the application demands shorter ramp-down time so I decided to order breaking module and breaking resistor.

I configured it via Sinamics configurator for my V20 2,2 kW - 6SL3210-5BE22-2UV0

• 6SL3201-2AD20-8VA0
• 6SL3201-0BE21-0AA0

I looked the Sinamics V20 manual regarding  wiring and that is clear.

You suggested to disable V_dc_max controller ? Is that ok? 

Is there any other parameter to be changed expect ramp-down time which should be reduced?

What is the recommendation for adjusting Duty cycle control knob on breaking module?

• 5: 5% duty cycle
• 10: 10% duty cycle
• 20: 20% duty cycle
• 50: 50% duty cycle
• 100: 100% duty cycle

https://cache.industry.siemens.com/dl/files/866/109773866/att_1007343/v1/V20_dynamic_braking_prod_info_1019.pdf

Technology Team

Hi,

as Piscean wrote, increasing the ramp down time is one solution.
Another would be activating the V_dc_max controller, which expands the ramp down time depending on the DC link voltage.

The best solution would be a brake unit with 6SL3201-2AD20-8VA0 an attached resistor hence the V_dc_max controller needs to be disabled

Please find section B1.3 and 1.4 in the V20s manual for selection, connecting and commissioning