Hello,
I haven't posted in a while, my history is that I am a noob.
Ok, we have an existing machine with an indexing table being run off an AC motor with no feedback. It rotates until a limit switch is set and this gives the motor the 'start' and 'stop' commands.
Well, as luck has it, it's overshooting every so often. Since we have no feedback, there is basically no way to verify it's overshooting situation.
SO, here's my problem. My boss wants to change the motor to a DC motor so we can easily vary it's speed using an existing variable motor speed controller that we had laying around ( ). On a positive note, it is a decent module (Camco Vari-Pak) that takes AC in and outputs a friendly DC out including some acceleration considerations.
So, where are we now? We have an AC motor (3 phase, 1HP) being controlled by a single logic output telling a contactor to turn on (Telemecanique LC1D09BD). This is funneled thru it's respective fuses as well as an overload protection module (Telemacanique GV2P06) to tell the logic if the motor has overloaded (I am assuming here). Part of the system also includes a Telemecanique LADN11 module that I have NO idea what it does.
So, basically, we need this thing to stop overshooting. I am quite the noob, seriously. I don't want to be screwing with logic just yet as I have never programmed ANYTHING and this machine is online right now. I understand logic well enough and I know how to read the drawings (assuming they're right) to see how to add logic to where I need it if necessary (I can requisition an electrical guy to do the changes for me if need be).
Adding feedback would be great but I don't think it's a good idea due to my lack of experience. Eventually, sure; today, I don't think so ESPECIALLY since I don't have the programming software nor do I have the existing logic (lucky me). Changing to a DC motor I don't think will fix any problems with our current setup but, again, I am requesting divine intervention if possible.
So, he wants a plug and play fix for our problem. Ideally, in his eyes, we take out the old motor, remove the contactor, feed AC into our motor speed controller, and slow down this new motor on the shop floor until it works (it has a big knob on top). It seems like a band-aid to me but I don't know the magnitude of how bad this problem is. This appears to be of a similar problem to pstephens 'the source weighs a lot' problem that may have caused overshoot. However, since our motor has no speed-up / slow down feature, it's relying on luck.
Any reply is appreciated, this is the first 'job' I have had so far.
I haven't posted in a while, my history is that I am a noob.
Ok, we have an existing machine with an indexing table being run off an AC motor with no feedback. It rotates until a limit switch is set and this gives the motor the 'start' and 'stop' commands.
Well, as luck has it, it's overshooting every so often. Since we have no feedback, there is basically no way to verify it's overshooting situation.
SO, here's my problem. My boss wants to change the motor to a DC motor so we can easily vary it's speed using an existing variable motor speed controller that we had laying around ( ). On a positive note, it is a decent module (Camco Vari-Pak) that takes AC in and outputs a friendly DC out including some acceleration considerations.
So, where are we now? We have an AC motor (3 phase, 1HP) being controlled by a single logic output telling a contactor to turn on (Telemecanique LC1D09BD). This is funneled thru it's respective fuses as well as an overload protection module (Telemacanique GV2P06) to tell the logic if the motor has overloaded (I am assuming here). Part of the system also includes a Telemecanique LADN11 module that I have NO idea what it does.
So, basically, we need this thing to stop overshooting. I am quite the noob, seriously. I don't want to be screwing with logic just yet as I have never programmed ANYTHING and this machine is online right now. I understand logic well enough and I know how to read the drawings (assuming they're right) to see how to add logic to where I need it if necessary (I can requisition an electrical guy to do the changes for me if need be).
Adding feedback would be great but I don't think it's a good idea due to my lack of experience. Eventually, sure; today, I don't think so ESPECIALLY since I don't have the programming software nor do I have the existing logic (lucky me). Changing to a DC motor I don't think will fix any problems with our current setup but, again, I am requesting divine intervention if possible.
So, he wants a plug and play fix for our problem. Ideally, in his eyes, we take out the old motor, remove the contactor, feed AC into our motor speed controller, and slow down this new motor on the shop floor until it works (it has a big knob on top). It seems like a band-aid to me but I don't know the magnitude of how bad this problem is. This appears to be of a similar problem to pstephens 'the source weighs a lot' problem that may have caused overshoot. However, since our motor has no speed-up / slow down feature, it's relying on luck.
Any reply is appreciated, this is the first 'job' I have had so far.
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