Hello All,

I would like to know if anyone has ever seen a Hour meter, that with an input like from a contactor, can measure the hours a device like a motor has been working, but that this one also have a output to send to the plc the amount of hours measured. The output can be discrete, analog or preferable with comms like rs485 modbus rtu.

 

Why not just have the PLC keep track of the hours and drive a small serial display if you don't have any other display?

Regards
cww

 

Yes, I know that you say is better and more practical, but my customer wants that the other way, and you know, customer is always right.

 

I haven't seen a self-powered hour meter like that, and I have looked for them in the past. If they don't exist I suspect the reason is that if anyone is going to go to those lengths (and expense) they would probably go a little further and network the controls so they can log the run-time in a central database for use by an automated maintenance software package that will do the reporting and scheduling as well. If such a maintenance software package applies some minimal intelligence it will detect time intervals whenever there is an "unreasonable" change in accumulated hours and adjust the figures with only a small loss in accuracy.

As for the question as to why not store the time in a PLC, if you download the PLC program again you may no longer have the correct accumulated hours. A self-powered hour meter will never get reset and will last for many years.

 

> I would like to know if anyone has ever seen a Hour meter, that with an input like from a contactor,
> can measure the hours a device like a motor has been working, but that this one also have a output
> to send to the plc the amount of hours measured. The output can be discrete, analog or preferable
> with comms like rs485 modbus rtu.

It has been a few years since this post was active. Any new hardware out there?