Carel µAM User Manual page 52

Example of operation
e-drofan master #1: probe 16 °C, set point 22 °C, difference: -6 °C, AUTOMATIC mode - heating
e-drofan master #2: probe 14 °C, set point 23 °C, difference: -9 °C, AUTOMATIC mode - heating
e-drofan master #3: probe 21 °C, set point 18 °C, difference: +3 °C, AUTOMATIC mode - cooling
Ch02 = 3 °C.
average: [(16-22) + (14-23) + (21-18)] / 3 = -4 °C.
The resulting sign is negative, the average without sign (4 °C) exceeds the value of parameter Ch03 (3 °C):
thus activates heating mode for the µC
µAM
Note: master e-drofan #3, if not fitted with a coil temperature probe, will start the fans, as it is in cooling
mode and the temperature measured by the probe is greater than the set point, however the air delivered
will be hot rather than cold, as required.
e-drofan set points and settings
µAM
e-drofan set point
centralised by µAM (overwritten every minute with the value
of the µAM set point)
centralised by µAM (overwritten every minute with the value
of the µAM set point)
can be set individually for each e-drofan
4.2.6 Activating the Compensation function
By activating this function, the µAM can dynamically modify the water temperature set point on the chil-
ler/hp when the ambient temperatures approach the set point, thus improving efficiency, with consequent
energy saving.
Important
• µAM acquires, via the RS485 data line, the limits for setting the set point saved in the µC2SE.
Parameters:
- r13 and r14 (COOLING)
- r15 and r16 (HEATING).
• The default values for these parameters allow the water set point to be set to potentially damaging values
for the chiller/hp unit, and in addition are not suitable for the optimum operation of the compensation
function.
• The µAM does not check the validity of these limits. The parameters in question must be checked by the
manufacturer of the chiller/hp unit based on the technical specifications of the unit and the correspon-
ding range of safe operation.
Information on the function
• It is only available for installations with the µC
• The function can be activated and the behaviour set using parameters Co01 (activation and type of
logic), Co02 (ambient temperature band for compensation in cooling), Co03 (ambient temperature
band for compensation in heating).
• The activation of this function, unlike the previous "Changeover" and "Energy Saving" functions, does not
require MODE to be set to AUTO.
• In the periods in which the µAM sets Dehumidification mode on the µC
tion function, as this is incompatible: in fact, Dehumidification mode is activated by setting a different
water temperature set point (Dehumidification set point) on the µC
point.
Procedure
1. To activate the function, set parameter Co01 (to access the parameters, see the chapter on "Parameters")
to one of the two values available (see further on: Operating logic);
2. The default values for parameters Co02 and Co03 are already suitable for the correct operation of the
function; to change them (Co03 only if the chiller is also a heat pump), start from the value of the fan
activation thermostat differential set on the e-drofan, multiplied by 2.
In this mode, the chiller/hp will work at maximum capacity only for ambient temperatures that are reaso-
nably "away" from the set point.
To deactivate the function, set parameter Co01 to 0.
OPERATING LOGIC (Co01= 1,2)
• (Co01=1): "Based on the average of differences between the e-drofan probe readings and the
corresponding set points"
How it works
When the chiller/hp unit is operating in HEATING (COOLING) mode,
rences, including the sign, between the readings of the temperature probes and the set points on the master
e-drofan units that are ON and without alarms, considering only those that are in HEATING or AUTOMATIC-
HEATING mode (COOLING or AUTOMATIC-COOLING); the sum is divided by the total number of master
e-drofan units that are ON and without alarms; the resulting value is used as the starting point to adapt the
water temperature set point of the chiller/hp, based on the graphs shown in the following figures.
20
SE.
2
Ch01
2
any
0, 1, 3, 4
2 SE connected.
SE, it suspends the compensa-
2
SE rather than the normal control set
2
calculates the sum of the diffe-
µAM
µAM +030220460 rel. 1.0 - 08.05.2007
Co01
any
2
0, 1
Tab. 4.c