Braking chopper capacity

Where can be found the official information regarding the braking chopper peak and continuous current capacity for power modules of G120C, G120, G130, S120?

The best I could get was from the braking resistors for example:
PM240-2 6SL3210-1PE31-5AL0 has a motor current capacity of 145A.

The file from this location suggests 3,85kW@100%ED and 77kW@5%ED for the resistor which I assume implies the maximum braking capacity of the drive.
https://cache.industry.siemens.com/dl/files/600/109749600/att_927508/v1/G120_PM2402_hw_inst_man_0617_en-US.pdf

The braking capacity of the chosen braking resistor is given in the specs for the resistor system.  The maximum braking capacity can be increased by a network of braking resistors that achieve the same overall equivalent braking resistance up to some theoretical maximum.

Are you asking about the capacity of a single braking resistor, or a maximally effective braking resistor network?

You can search these forums for how to build braking resistor networks to increase capacity.

If you are doing research for a new system and braking is important, purchase regen capable power modules for G120 drives, or appropriate regen setup for larger drives.

Regen systems can absorb much more motor power over shorter periods of time than DC brakes.  For example, something needs to slow down in under 1 second - without faulting the drive and coasting the motor.  A DC brake may not be capable of doing that.  A regen system has a better chance of it provided everything is sized properly.

Refer to the online Siemens Sinamics Sizer application where you can perform calculations on the dynamics of your system and get a parts list of components capable of meeting those dynamic requirements.

samuelbb

Where can be found the official information regarding the braking chopper peak and continuous current capacity for power modules of G120C, G120, G130, S120?

The best I could get was from the braking resistors for example:
PM240-2 6SL3210-1PE31-5AL0 has a motor current capacity of 145A.

The file from this location suggests 3,85kW@100%ED and 77kW@5%ED for the resistor which I assume implies the maximum braking capacity of the drive.
https://cache.industry.siemens.com/dl/files/600/109749600/att_927508/v1/G120_PM2402_hw_inst_man_0617_en-US.pdf

My question is about the integrated braking chopper, not the resistor. 

How much can the braking chopper handle continuously and also in peak "dynamic braking". This information is not in the manual. Is it public?

The standard Pdb and Pmax are values for the resistor which may not represent the chopper values. Assuming they do indirectly represent maximum chopper values (for PM240-2) I feel they are inadequate (dissipation power is 6% of the nominal power PM) for applications with large inertia or high speed, and low dynamic requirements. Something around 20% would be better (for my needs).

And depending on the drive model, I know the chopper activation voltage can be changed, or the duty cycle of the chopper can be changed. Add a line voltage different from nominal, and the braking resistor values (ohm and power) needs to be adjusted.

PM250/ALM is not the solution I need.

0_Einstein

The braking capacity of the chosen braking resistor is given in the specs for the resistor system.  The maximum braking capacity can be increased by a network of braking resistors that achieve the same overall equivalent braking resistance up to some theoretical maximum.

Are you asking about the capacity of a single braking resistor, or a maximally effective braking resistor network?

You can search these forums for how to build braking resistor networks to increase capacity.

If you are doing research for a new system and braking is important, purchase regen capable power modules for G120 drives, or appropriate regen setup for larger drives.

Regen systems can absorb much more motor power over shorter periods of time than DC brakes.  For example, something needs to slow down in under 1 second - without faulting the drive and coasting the motor.  A DC brake may not be capable of doing that.  A regen system has a better chance of it provided everything is sized properly.

Refer to the online Siemens Sinamics Sizer application where you can perform calculations on the dynamics of your system and get a parts list of components capable of meeting those dynamic requirements.

The standard braking resistor ohms value allow for more power than what the braking chopper can handle.

The PM240-2 1PE26 with standard 15ohms may dissipate +34kW if allowed. The braking chopper burns before failure of the cables/resistor. Real world experience.

Some applications do not require fast stop with peak braking power.
Some applications need average braking power.
In some instances the braking chopper parameters may be incorrectly configured.
In some instances the braking chopper controller misbehaves.

Those situations would benefit from an average power ohm value sized resistor and from having it as a passive safety feature. Even if the CU is misconfigured or the controller misbehaves there will not be failure of the braking chopper (it fails short-circuited) and eventual failure of the front-end and total loss of the drive. 

The corresponding value for the example I'm using is ~280ohms, but as said before 6% (1850W/30kW) braking power is small. If the drive could handle more, and if this information is public, then I (and others) could correctly size the resistor for my needs.

Hati

uhm... basically the brake chopper is not the limiting factor on the breaking, the resistor is.