Endress+Hauser Proline Promag 55 Operating Manual page 45

Device Functions Proline Promag 55 FOUNDATION Fieldbus
Endress+Hauser
BASIC FUNCTION
PRESSURE SHOCK The closure of a valve can cause brief but severe movements of the fluid in the piping
SUPPRESSION system, movements which the measuring system registers. The pulses totaled in this way
(6404) result in a totalizer reading error, particularly in the case of batching processes. For this
reason, the measuring device is equipped with pressure shock suppression (= short-term
signal suppression) which can eliminate system-related "disruptions".
!
Note that pressure shock suppression cannot be used unless the low flow cut off is active
(see ON-VALUE LOW FLOW CUT OFF function on Page 44).
Use this function to define the time span for active pressure shock suppression.
Activation of pressure shock suppression
Pressure shock suppression is activated once the flow falls below the switch-on point of
the low flow cut off (see point a in graphic).
While pressure shock suppression is active, the following conditions apply:
• Flow reading on display → 0
• Totalizer reading → The totalizers are pegged at the last correct value.
Deactivation of pressure shock suppression
The pressure shock suppression is deactivated after the time interval, set in this function,
has passed (see point b).
!
The actual flow value is displayed and output, when the time interval for the pressure
shock suppression has passed and the flow exceeds the switch-off point of the low flow
cut off (see point c in graphic).
m = on value (low flow cut off), n = off value (low flow cut off)
a
b
c
■
Q
User input:
Max. 4-digit number, incl. unit: 0.00 to 100.0 s
Factory setting:
0.00 s
Function description
→
PROCESS PARAMETER
Note!
Note!
Q
Command:
Valve closes
After filling
a
n
m
inactive
Activated when the on-value for low flow cut off is undershot
Deactivated once the time specified expires
Flow values are taken into account again for calculating the pulses
Suppressed values
Flow
7 Block BASIC FUNCTION
→
CONFIGURATION
Pressure shock suppression
b c
active
inactive
Given time
t
A0001285-EN
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