EcoRenovator - View Single Post - Daox's diy arduino thermal differential controller

stevehull · 04-24-14, 06:03 PM

Daox,

You need to put in hysteresis. This is essentially a "dead zone" where the controller is off. No matter how precise the controller, without a dead zone, you will get cycling.

An alternative is to "forward load" the system to negate an immediate response and to wait for some period of time to check to see if an output is really needed. If in two minutes, the system still calls for blower, then it will cycle, but not on the first try.

Both are examples of hysteresis in a control system.

Does this make sense?

Steve

04-24-14, 06:03 PM	#35
stevehull Steve Hull Join Date: Dec 2012 Location: hilly, tree covered Arcadia, OK USA Posts: 826 Thanks: 241 Thanked 165 Times in 123 Posts	Daox, You need to put in hysteresis. This is essentially a "dead zone" where the controller is off. No matter how precise the controller, without a dead zone, you will get cycling. An alternative is to "forward load" the system to negate an immediate response and to wait for some period of time to check to see if an output is really needed. If in two minutes, the system still calls for blower, then it will cycle, but not on the first try. Both are examples of hysteresis in a control system. Does this make sense? Steve __________________ consulting on geothermal heating/cooling & rational energy use since 1990 Last edited by stevehull; 04-24-14 at 06:24 PM..