What Does No Control Voltage Mean?

[travis]

What Does No Control Voltage Mean?

I have seen this error on a servo motor control system. Is there a simple explanation? I checked the control voltage and I have the 24 Volts so it is confusing. I shouldn't see a "no control voltage error".

[Cheller]

If you have a no control voltage fault or alarm, common sense tells me the control voltage is absent. If you've checked your control voltage and it is present, I would say that you're looking in the wrong place, or the system requires more than one control voltage (maybe 12V, 5V, etc)

The other possibility is that the circuit, or input point, that senses the control voltage has failed and it thinks there isn't any voltage. You need to dig deeper and study the schematic.

[3rdshiftguy]

Here's my take on "What does no control volts mean?"

This alarm is exactly what it says...The control voltage is missing or was interrupted momentarily. This can be caused by many things, most of which can be identified with a voltmeter.

• The control's AC line voltage is absent or was briefly interrupted. You can't generate control voltages without an input voltage..


• Blown fuse or tripped circuit breaker either on the primary or secondary side of the power supply.


• Remember, there can be more than one control voltage in a system (ie 5v, 12v, 24v) so a "no control volts fault" can mean that only one of these is missing.


• The voltage signal that feeds the control voltage monitor is not present. This is the least common problem but can get you if you're not paying attention.