VRP-M VAV
Adaptive VAV controller
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Product information S4-VRP-M VAV • en • v2.0 • 11.2006 • Subject to changes
www.belimo.eu
Functions
(Continued)
Control tolerance
The maximum permissible control tolerance is defined as a percentage of the nominal volumetric
flow nom. If the system deviation exceeds or undershoots this tolerance, the actuator is adjusted
so that the volumetric flow actual value corresponds to the required setpoint.
Control tolerance: ±5% of
nom
The two LEDs [+p] and [-p] indicate when the maximum control tolerance is exceeded or under-
shot or when the deviation is being corrected by means of an actuator movement:
LED [+p]: Volumetric flow actual value > (se control tolerance) = damper closes
LED [-p]: Volumetric flow actual value < (se control tolerance) = damper opens
VAV operating volumetric flow
min
...
max
setting
In variable operation, the volumetric flow is specified by means of the reference signal in the
min
...
max
range.
–
max
forms the upper limit value as a function of the nominal volumetric flow.
Range 30 ... 100% of
nom
.
–
min
forms the lower limit value as a function of
nom
.
Range 0 ... 100% of
nom
.
Voltage level
0,0
10
0,0
0,1
10
2,0
min
0…10 V
2…10 V
max
max
min
In mode 2 ... 10 V, it is possible to achieve shut-off mode (damper CLOSED) by lowering the
reference signal to 0.0 V.
For override control in VAV operation, for example CLOSED or OPEN, the reference signal w
(input 3) can be overridden by connecting control inputs 6 (z1) and 7 (z2).
CAV operating steps
CLOSED /
min
/
mid
/
max
/ OPEN
Five operating steps are available for step operation:
– Shut-off operation – damper CLOSED: The damper is moved into the CLOSED position in a
defined manner.
– Operating steps
min
/
mid
/
max
: The VRP-M adjusts the volumetric flow to the fixed selected
value.
– Flushing operation – damper OPEN: The damper can be opened for maximum ventilation, in
which case air volume control is deactivated.
The operating mode control signals are connected to inputs 6 (z1) and 7 (z2). If signals appear
at these two inputs simultaneously, input 6 (z1) for the OPEN function takes priority.
Reference signal w
[V]
nom
max
[
min
]
Variable operation
Volumetric flow [%
nom
]
Volumetric flow actual value signal U5 [V]
Ex
am
ple: 0 ... 10 V mode
< Modulating operation >
Start point
End point
Shut-off
[
max
]
Mode:
CLOSED
< Modulating operation >
