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Changing anti-cycling period

Hello everyone, Hope you are all in good health and high spirit.

I'm trying to understand why my single speed dx-coil action is delayed at higher cycling frequencies. It seems that the coil is having an anti-cycling period of about 3.5 minutes from the results I've tested. But I can't find that in the manual to confirm. Where can I find this in energyplus documentation ? and is there a way I can change this value ?

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Thanks and stay safe !

Aly ElHefny's avatar
482
Aly ElHefny
asked 2020-07-02 21:49:58 -0500
__AmirRoth__'s avatar
4.4k
__AmirRoth__
updated 2020-07-03 17:51:03 -0500
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What "order" did you give?

rraustad's avatar rraustad (2020-07-02 21:54:49 -0500) edit

turn on cooling coil

Aly ElHefny's avatar Aly ElHefny (2020-07-02 21:56:10 -0500) edit

Well, of course, but how did you command the coil to turn on? EMS? External Interface?, etc.

rraustad's avatar rraustad (2020-07-02 21:57:16 -0500) edit

External interface, so give order on = (availability = 1 and SP is lower the current temperature at a desired value), are there built-in anti-cycling periods in energyplus ?

Aly ElHefny's avatar Aly ElHefny (2020-07-02 21:58:58 -0500) edit

Perfect. This gives other viewers some perspective on your method. Unfortunately I am not a user of external interfaces. I do know the coil models pretty well. Could you provide a more macro level plot of temp vs time when using a "detailed" reporting frequency so that we can see the response in real (simulated) time? Maybe that won't help but I don't know until I see it.

rraustad's avatar rraustad (2020-07-02 22:05:30 -0500) edit
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1 Answer

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Without knowing what time scale the interface is using with E+, I will explain that if the zone temperature changes by more that 0.3 C then the HVAC time step in E+ will be reduced proportionally to the temperature change. So for example, if your time step is 10 min, and the change in zone temp is 1 C, then the HVAC simulation time step will be reduced to 3.33 minutes. What you need to do is view temperature vs time using the most detailed time step possible.

rraustad's avatar
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rraustad
answered 2020-07-02 22:35:05 -0500
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I'm both simulating and viewing at 1 minute timestep. Is there a built-in anticycling period in energyplus ? because I've been searching the manuals and didn't have luck in confirming this point.

Aly ElHefny's avatar Aly ElHefny (2020-07-03 00:38:37 -0500) edit

I am not aware of any anticycling in E+. Use a detailed reporting frequency as: Output:Variable,*,Variable Name,Detailed;

rraustad's avatar rraustad (2020-07-22 10:06:54 -0500) edit
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