Question-and-Answer Resource for the Building Energy Modeling Community
Get started with the Help page
Ask Your Question
1

Changing anti-cycling period

asked 2020-07-02 21:49:58 -0500

Aly ElHefny's avatar

updated 2020-07-03 17:51:03 -0500

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 ?

image description

Thanks and stay safe !

edit retag flag offensive close merge delete

Comments

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

1 Answer

Sort by ยป oldest newest most voted
1

answered 2020-07-02 22:35:05 -0500

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.

edit flag offensive delete link more

Comments

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

Your Answer

Please start posting anonymously - your entry will be published after you log in or create a new account.

Add Answer

Training Workshops

Question Tools

1 follower

Stats

Asked: 2020-07-02 21:49:58 -0500

Seen: 82 times

Last updated: Jul 02 '20