Honeywell EXCEL 5000 User Manual page 185

EXCEL CARE CONTROL ICONS ALPHABETIC REFERENCE
EOV shuts down the system without advance when the actual OAT is less than or
equal to the minimum OAT (Parameter P5). Between these limits, EOV calculates
advance time (T VHA ) as follows:
Where t corr = (X3 - X2) * P6
In other words, the correction factor equals room temperature minus setpoint
multiplied by the optimum stop factor.
The correction factor changes the slope of the previously defined characteristic
curve as a function of the control difference:
If room temperature equals room temperature setpoint, the characteristic curve
remains unchanged.
If room temperature is greater than room temperature setpoint, the characteristic
curve is steeper and the system is shut down earlier.
If room temperature is less than room temperature setpoint, the characteristic curve
is less steep and the system is shut down later.
The following figure illustrates this relationship.
Parameter P6 (optimum stop factor) weights the influence of the control difference
on the characteristic curve. If Parameter P6 is zero, EOV calculates early shutdown
based on OAT only.
Optimized Start-up in the Cooling Mode
When the system is in cooling mode (XD5=0), EOV displaces switch-on point
(start-up) by time (t VKE ) to guarantee room temperature setpoint is reached by
start-up. The displacement of the switch-on point depends on the difference
187 74-5577–33 (US)
EN2B-0184 GE51 R0518 (Europe)