Klimor EVO -T, Operation And Maintenance Manual

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AUTOMATION AND CONTROL SYSTEM FOR UNITS
EVO-T; EVO-T COMPACT
OPERATION AND MAINTENANCE MANUAL
Fig. 23
Setting of heater stages
Additionally it is possible to limit the max adjustment
value for the PWM signal of the SSR relay. They are con-
trolled by means of changing settings of the P3 pot.
Fig. 24
Potentiometers settings
The P1 and P2 pots enable narrowing down the system
operation range in relation to the full 0÷10V signal scale.
This solution enables the application of one 0÷10V signal
to control two multistage electrical heaters.
The N=P2-P1 difference cannot be smaller than 10% for
each selected heating stage (e.g. for 1 level: N ≥ 10%, for
6 levels: N ≥ 60%). If due to the pots setting the N differ-
ence is lower than the required value, then the system
triggers an alarm.
Sample module setting:
The 3-stages P=36kW (12kW/stage) electric heater is fit-
ted. The rated heating power required to heat the build-
ing is Pn=20kW.
As standard the module is supplied in a configuration
enabling usage of the max. heater power. The first step
is to define the min. number of operating stage of the
heater. The sum of power values of active stages must be
higher or equal to the Pn power. In our case the power of
2 stage is sufficient. The dip-switch should be set to the
position of stage 2.
Then you should calculate the PWM limit value in ac-
cordance with the following formula:
where:
P3 – calculated PWM signal limit
N – number of activated stages
P1st – power of a single stagel of the heater [kW]
Pn – power required for the building [kW]
By substituting into the formula:
The P3 pot should be set to 66%.
11.2 First start-up
• Read this manual as well as the AHU control system man-
ual.
• Check and start the AHU control system, and then con-
nect power supply and control of the EH module as well
as power supply of the heat output stages, in accordance
with the AHU application diagram and the EH module di-
agram.
• Switch on power supply of the AHU control cabinet and
the EH module.
• Set a number of heater levels at the EH module controller
• Check operation of the system.
Wiring diagrams of the EH EVO-T 36kW/3 and 54kW/3
modules can be found in section 12.
Fig. 25 Workflow of heating adjustment
Start of the heater is absolutely blocked by the
heater safety thermostat (connected to the HE
module) and by the signal from the fan pressu-
re gauge (connected to the HE module), which
have to be connected in accordance with the
wiring diagram. Reaction of the ventilation
system in case of the overheating alarm or lack
of signal from the fan pressure gauge is descri-
bed in point 8.4 „Alarms” since both control
boxes make up one complete control module.