CAD CAM EDM DRO - Yahoo Group Archive

Re: DUMP CIRCUIT

Posted by caudlet
on 2005-02-19 08:52:28 UTC
--- In CAD_CAM_EDM_DRO@yahoogroups.com, "deepcavity"
<deepcavity@h...> wrote:
> Can anyone tell me more about the Power Dump Circuit. I
have software from Ah-Ha
> Allan
>
> [Non-text portions of this message have been removed]

The Power Dump (or Over Voltage Protector [OVP]) circuit is a form of
shunt regulator. It has nothing to do with the software. It's total
purpose it to protect the motor driver modules from exceeding their
maximum recommended voltage spec. One of the issues with driven
motors is they are also generators so if they are being mecahnically
driven (like during a rapid decelleraton) they switch to being
generators and produce a back (reverse) voltage that can add to the
unregulated raw DC and potentially raise the level above the unit's
SOA (Safe Operational Area). This only becomes an issue where you
are running raw DC volatges that are close to the max specs of the
motor drivers.

The power dump monitors the voltage and if it exceeds the preset
amount diverts the voltage into a resistive load. It essentially
places a heavy temporary load in parallel with the motors
and 'shunts' the current to negative and dissipates it as heat.
During normal operation the only current drawn by the circuit is the
tiny amount to run the voltage comparitor.

OVP's and Shunt regulators are a common application in power
electronics.

Discussion Thread

deepcavity 2005-02-19 08:35:07 UTC DUMP CIRCUIT caudlet 2005-02-19 08:52:28 UTC Re: DUMP CIRCUIT