Re: [CAD_CAM_EDM_DRO] Re: Gecko E-Stop recommended configuration

Mariss,

Thank you for your help on the Estop. I guess the cap voltage rating can be
around 100 volts on an 80 v system?

The purpose of the capacitor is to supress arcing on the contacts, I take
it.

Did you get a chance to glance at Doug Harrison's fault circuit that I faxed
you?

Gratefully,

Tom Eldredge

----- Original Message -----
From: <mariss92705@...>
To: <CAD_CAM_EDM_DRO@yahoogroups.com>
Sent: Wednesday, June 06, 2001 5:10 PM
Subject: [CAD_CAM_EDM_DRO] Re: Gecko E-Stop recommended configuration


> Tom,
>
> Brush DC motors are able to run without benefit of any electronics,
> step motors are not. Brush DC servo systems are equiped with
> protection circuits to prevent against most runaway faults but not
> all, such as a shorted transistor.
>
> The only sure fire way to stop a motor is to remove power from it.
> The question is how.
>
> 1) Shut off the AC input to the supply. This is easiest on the switch
> and the drives but the power supply filter capacitor "hold-up" time
> may be a second or more.
>
> 2) SPDT switch in the DC supply circuit. Common to the drive's "+"
> supply input, N.C. to the power supply "+" terminal, N.O. to the
> drive's "-" supply. This has the benefit of dynamically breaking the
> motor after disconnect from the power supply. The switch contact
> rating is higher and there must be at least a 1,000 uF capacitor
> across the drive's power supply inputs at the drive. This is tough on
> the cap and switch.
>
> 3) For more mundane (non-emergency) faults in multiple axis setups
> please see the "4 axis reset manager" pdf in the "files section of
> this group.
>
> Hope that helps. I am writing an applications section for the servo
> drives. It should be finished in a few weeks. I am trying to keep it
> from having as many pages as Tolstoy's "War and Peace".
>
> Mariss
>
> --- In CAD_CAM_EDM_DRO@y..., "Tom Eldredge" <harmonyt@r...> wrote:
> > Mariss, and other Gentlemen,
> >
> > If this has not been already covered, do we need an application
> note on this subject?
> >
> > Many of us are using or are planning to use the G320, 340 drives.
> What is the recommended proceedure for E-stopping a G320 servo loop?
> It is my understanding that for safety reasons, the power is to be
> removed from the motor/drive, and IC logic is not to be depended upon
> to actually stop motion in an emergency situation. If so, where
> should we put in the relay to do so, in the power line to the amp, or
> inside the motor/drive loop? If not, should we simply use the
> disable input to the drive for emergencies?
> >
> > Thanks again,
> >
> > Tom Eldredge
> >
> >
> >
> > [Non-text portions of this message have been removed]
>
>
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