GE Fanuc 90-30 HSC as oscillator

In the High Speed Counter Manual it shows where the HSC can be used for Timing Pulse Generation. I need to verify I am understanding this correctly.

I have the need to setup a test bench for some stepper motors, I have a driver to use but I need to pulse it (a fixed frequency is fine but need high frequency to make it run smooth/fast).

Tell the truth I am not sure what question to ask. I setup the HSC to match what is in the manual but now I have gotten lost. How can I use this externally as an oscillator to drive my stepper motors?

As I said I have confused myself somehow and not sure what I need now.

IF anyone can give me a hint to jog this old head into action then it will be highly appreciated.

I realize there are other items that would work for this purpose but I have MANY GE 90-30 and was hoping to use one of them.

Thanks for any help you may offer.

The 90-30 HSC has an internal oscillator that can be used as a count input for counter number 1. Configure your module as a type A counter, and set the Oscillator Input ON. For counter 1, if you set the count mode to continuous, low limit to zero, high limit to 9, and on preset to 5, the counter will cycle from zero to 9, with output 1 being off from zero through 4, on from 5 through 9. That will give you a square wave pulse on output 1 at one tenth the oscillator frequency.

The default oscillator frequency is 1 Khz. You can modify it in configuration. To modify while your program is running, you need to send a COMREQ to the HSC. COMREQs can be a royal PITA, so I won't get into it here.

I didnt use your numbers but thats basically what I did.

I set the divider to 66 which is suppose to be 10khhz which is a 5000 count (0 - 4999).
Counter Type A
Oscillator Frequency Divider=66
Oscillator Frequency Input=ON (1)
mode=continuous
high limit=4999
low limit preset=0
On preset=2499
Off preset=0
I figured this would give me an output at 1/2 the oscillator frequency which for my purpose should be excellent.

Silly question, should you be able to "see" that output with a frequency meter or scope without it being attached to a load?

I dont seem to be getting the output, the plc with card is a system pull so it may have problems. Just wanting to verify that I was on right track.

The outputs require external power. DC+ on terminal 14, DC- on terminal 20, Output 1 on terminal 16. The outputs are positive logic (sourcing).

Also, you must enable the output by setting the ninth %Q bit assigned to the module. If the module is addressed to %Q0017, then the enable bit for output 1 would be %Q0025. The ninth %I bit assigned to the module mirrors the state of the output, so if you've configured the module for %I0017, then %I0025 will be on when the accumulated count is at or above the preset.

With the numbers you're using, output 1 should be a 2 Hz oscillator, and you should be able to see it with a scope. You should be able to see the internal oscillator frequency in the second %AI register assigned to the module. If the module is configured to %AI001, then the counts per timebase value for counter number 1 shows up in %AI002. The accumulated count shows up in the sixth %AI register.

I set up a VVT and I can see the AI6 register numbers going to town.

I have the moduled wired as you stated
+24 on 14
Com on 20
OUT1 = 16

The card is in first slot of 5 base so when I configured it auto set
%I0001
%Q0001
%AI0001

I just aint gettin no output, once again I know I am overlooking the obvious.

Did you set %Q0009 ON?

That was a DUH, I turned on Q10 but I had the pulse lead wired to connector wrong also, wasnt using positive logic

Thanks I got it
I set Divider to 66
High limit =9
Preset On =4

I have it running and the speed is at an acceptable level but I am not sure I truly understand what I have done. The numbers involved with the HSC in the HWC have me a little confused.

I will RTFM some more and more, maybe the light bulb will come on. While I am messing with this thing i may just go ahead and try different things with it as an experiment. I have more than one so I can take this setup and place on test bench.

Another thing to remember about the HSC: The outputs are only updated every 500 microseconds, so you're at the maximum output frequency with your current settings. The oscillator divider setting of 66 gives you a count frequency of 10 KHz in the accumulator. Your low limit of 0 and high limit of 9 gives you a 10-count cycle in the accumulator (1 Khz). Setting the preset at 5 means that the physical output associated with the accumulator (Output 1) will be ON for half of the cycle, OFF for the other half.

I have a 90-30 and a HSC module on my bench. Call me if you want to talk through the option settings to get a better understanding of what they mean. We'll keep the end results on-forum, but I have a feeling that expertise in GE Fanuc 90-30 high speed counters is a rather obscure specialty in the universe of PLC applications. My former employer, the local GE Fanuc distributor still refers all application questions on HSCs to me, and I only get a handful of calls per year.

GE Fanuc and Stepper

rsdoran,
If you have an extra GE Fanuc Micro PLC, either the older Series 90 or the new VersaMax type. You will be able to drive you stepper drive from the first output of these. %Q1 can be configured as a PWM output or Oscilator out.

I have a Series 90 micro PLC, 14 PTS. Please give a hint on how to configure the HSC type A to monitor the speed of a worm gear using a proximity sensor as my input. In the user manual of user manual of the micro plc there is a example but to tell you the truth I cant understand on how to do the program and configuration. Please advice thanks.

Without more details it's hard to decide where to start. Wire your proximity switch to input 1. Configure the PLC as 4 Type A counters, make sure you enable counter #1 . Whether you enable the outputs or not is up to you and your application. The accumulated count will show up in %AI006. The count rate (counts per timebase) will be in %AI002. The default timebase is one second (1000 milliseconds).

I'll go back to the office on Monday and I will do what you have instructed me to do. I'll just post questions if i encountered problem.
Thanks Steve