Trox Control component Easy, Инструкции по установке и вводу в эксплуатацию

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Setpoint value adjustment independent of the duct
pressure
Fig. 6: Pressure independent control characteristics
The controller detects and corrects changes of the duct
pressure that may occur, for example, due to volume
flow rate changes from other units. The Easy controller
thus operates duct pressure independently and pres-
sure fluctuations result in no permanent changes in
volume flow rate.
In order to prevent the volume flow control from
becoming unstable, the controller maintains a dead
band (hysteresis) within which the damper blade is not
moved. This dead band and the tolerances of the meas-
urement location lead to a volume flow rate deviation
ΔV in accordance with the product data sheets of the
VAV terminal units. If the conditions specified in the
product data sheets (e. g. minimum differential pressure,
upstream conditions) are not met, greater deviations are
to be expected.
Diagnostic options
A function test is possible by means of test push button
(Fig. 1/8) and LED indicator light (Fig. 1/9). The LED
makes it possible to distinguish between operating and
fault states.
The diagnosis of setpoint value and actual value signals
is possible via multimeter, Ä Chapter 7.3.1 ‘Use of mul-
timeters to control setpoint values and feedback signals’
on page 29 .
Adjustment devices cannot be used for Easy controllers,
Ä Chapter 7.3.2 ‘Use of adjustment devices’
on page 29 .
3.5 Operating modes
3.5.1 Operation with constant volume flow
rate setpoint value
Operation with a fixed setpoint value
Fig. 7: Constant control
1 Volume flow rate setpoint value specification (V
min
)
2 Actual value volume flow rate as 0–10 V DC signal,
e. g. to the central BMS
In the simplest case, the controller is operated with a
constant volume flow rate setpoint value specification.
During commissioning, the setpoint value is set directly
on the rotary potentiometer (V
min
) on the Easy controller
(V
max
= 0%).
A control signal at terminal w is not required in this
case.
Structure and functional description
Operating modes > Operation with constant volume flow rate setpoint value
Control component Easy for VAV terminal units 13