I have a Bridgeport that I am retrofiting, Im told we should be able to controll the RPM and Breaking system.
The machine has one sensor for High/Low gear position.
One sensor for RPM's .
It has 3 valves that control the RPM's & Breaking.
Is there any information on how to wire this?
**RESOLVED** Bridgeport Spindle
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rfhowell68
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Re: Bridgeport Spindle
In past practice, Centroid has only provided manual control of spindle speed on machines like yours: the pneumatic speed-up and speed-down controls were mapped to buttons and/or keys, and the PLC would power the solenoids when you pressed the button, provided the spindle was running.
In past practice, if programmable spindle speed was required, then Centroid (and we Centroid dealers) recommended a VFD conversion.
With the All-in-one DC unit, you have an analog input to the PLC. You could theoretically wire the spindle speed feedback pot to the analog input (wire it as a voltage splitter, to provide 0-10VDC as it runs from minimum speed to maximum speed). You could then add code in the PLC program to compare the pot feedback to the desired spindle speed (the analog value that would normally have been sent to a VFD) and to run the speed-up and speed-down solenoids until the actual speed is close to the desired speed.
As far as I know no one has designed wiring and written PLC code to do that yet. Maybe you can be first.
In past practice, if programmable spindle speed was required, then Centroid (and we Centroid dealers) recommended a VFD conversion.
With the All-in-one DC unit, you have an analog input to the PLC. You could theoretically wire the spindle speed feedback pot to the analog input (wire it as a voltage splitter, to provide 0-10VDC as it runs from minimum speed to maximum speed). You could then add code in the PLC program to compare the pot feedback to the desired spindle speed (the analog value that would normally have been sent to a VFD) and to run the speed-up and speed-down solenoids until the actual speed is close to the desired speed.
As far as I know no one has designed wiring and written PLC code to do that yet. Maybe you can be first.