2 limi ta tion using 0/4 to 20 ma sig nal 62, 11 loc king manual levels 62, Using a 0/4 to 20 ma sig nal 62 – Samson 5476 User Manual

Page 62: Loc king ma nu al le vel 62, Limitation using 0/4 to 20 ma signal, Locking manual levels, 11 locking manual levels

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Functions

WE

Configuration

Current input for flow rate
measurement

OFF

FB22 = OFF

Flow rate or capacity limitation

OFF
500 pulse/h
1.0
500 pulse/h
1.0

FB23 = ON
Max. limit / 3 to 500 pulse/h
Limiting factor / 0.1 to 10
Max. limit for DHW / 3 to 500 pulse/h
Limiting factor / 0.1 to 10

7.10.2 Limitation using 0/4 to 20 mA signal

A connected heat meter (terminals GND/15 with a 50

W

resistor connected in parallel) with a

0/4 to 20 mA output can be used to limit the flow rate in the system. All limit values are given in
the unit “cubic meters per hour“ [m

3

/h]. As a result, it is necessary to se in addition to

Lower

measuring range value 0 or 4 mA also an Upper measuring range value (flow rate at which the
20 mA signal is issued) in unit [m

3

/h]. When the flow rate reaches the current

Maximum limit ,

the controller switches in control circuit RK1 to flow rate control with the

Maximum limit acting

as the set point. If the flow temperature exceeds its normal set point by more than 5 °C during
this time, the flow temperature control is started again. If the flow rate falls below the set

Mini-

mum limit, the control valve of control circuit RK1 is temporarily closed. The normal control op-
eration is started again when the flow temperature falls below its normal set point by 5 °C.

Note!
In systems Anl 4 to 6 and 11, the valve of the heating circuit is affected during an active flow
rate limitation.

Functions

WE

Configuration

Current input for flow rate measurement OFF

FB22 = ON, select “Lower measuring range”

Flow rate or capacity limitation

OFF

10.00 m

3

/h

0.01 m

3

/h

9.00 m

3

/h

FB23 = ON
Upper measuring range / 0.1 to 650 m

3

/h

Minimum limit/ 0.01 to 650 m

3

/h

Maximum limit / 0.01 to 650 m

3

/h

7.11 Locking manual levels

The number of access options to the controller can be restricted by locking the manual level.
When the locking is active, the mode switches positioned at the manual mode do not have any
effect concerning manual activation of the valves. Merely, reactions occur as if the mode

62

EB 5476 EN

System-wide functions

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