Author Topic: OutputMode 3 vs 6  (Read 3361 times)

Offline flno

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OutputMode 3 vs 6
« on: May 11, 2023, 02:21:09 PM »
What is the difference between .OutputMode 3 and 6?
- OutputMode 3: PWM Output, 0 - 10000 [0.01% pos duty]
- OutputMode 6: PVE Output, 0 - 10000 [0.01% of PVE Power]
I know that outputmode 6 is used for driving a ratiometric PVE, but from my point of view there are no difference between the two configuration. If I have 20VDC supply and give command for 50.00% Positive duty in outputmode 3, I will se and average voltage of 10VDC, as I would when using outputmode 6.

Offline Lukey

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Re: OutputMode 3 vs 6
« Reply #1 on: May 15, 2023, 10:43:23 AM »
Hi flno,

Yes correct OutputMode 6: PVE Output, 0 - 10000 [0.01% of PVE Power] is for driving Danfoss PVE radiometric coils.

OutputMode 3: PWM Output, 0 - 10000 [0.01% pos duty] is for driving any/generic PWM coils up to 4000hz and 3Amp, such as a proportional Cetop DCV or pressure relieving/reducing valve etc.

You will also need to use the correct Function Block for the OutputMode nominated.
There is dedicated PVE and PWM blocks found in the Outputs Library that can be used.

I wouldn't worry too much about the 10VDC you are reading I'm assuming is just the latency of your multimeter, I think you'd need a CRO to see the exact valves.

Offline FluidPowerTom

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Re: OutputMode 3 vs 6
« Reply #2 on: May 15, 2023, 05:01:29 PM »
I'm unaware of exactly what the difference is between the two output modes, 3 and 6.  They both appear to be duty cycle control.  My expectation is that mode 6 turns on some additional internal diagnostics and/or optimizes some parameters for the internal signal generator (such as PID loop) for specifically controlling PVE valves.

You would actually want to use mode 4 or 5 for drive any generic proportional Cetop DCV or other proportional valve.  The current control modes will yield more consistent results as the coil heats up or is ever replaced.

You actually don't need to use the 'correct' function block as was mentioned last.  It's recommended because those function blocks provide useful scaling and support diagnostic conditions well.  They save time.
Controls Engineer
Hydra-Power Systems

Offline flno

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Re: OutputMode 3 vs 6
« Reply #3 on: May 22, 2023, 10:24:37 AM »
Year that was also my thought, that there might be some logic for more precise voltage control, but I could not see the difference in practice. My application is to generate a fixed 0-10 volt reference signal for an external embedded valve controller. Then I was wondering which output mode to choose and could not see the difference in practice.

Offline flno

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Re: OutputMode 3 vs 6
« Reply #4 on: May 22, 2023, 10:27:59 AM »
Sorry, 2-10 Volt in this case

Offline Lukey

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Re: OutputMode 3 vs 6
« Reply #5 on: May 24, 2023, 03:31:10 AM »
The controllers are not specifically designed for industrial PLC type 0-10V output signals, check out this existing thread, FluidPowerTom gives a good example of how he has made it work.

https://www.plus1forum.danfoss.com/index.php?topic=1110.msg3527#msg3527