Issue/Rev. 0.2 (12/12) MN0M023 • Page 123
Device Functions Proline Promass 83 9 Block BASIC FUNCTION
PRESSURE SHOCK
SUPPRESSION
(6404)
The closure of a valve can cause brief but severe movements of the fluid in the piping
system, movements which the measuring system registers. The pulses totaled in this way
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!
Note that pressure shock suppression cannot be used unless the low flow cut off is active,
(see function ON-VALUE LOW FLOW CUT OFF on page 122).
Use this function to define the time span for active pressure shock suppression.
Activation of the pressure shock suppression
Pressure shock suppression is activated after 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:
• Current outputs o outputs the current corresponding to zero flow.
• Pulse-/Freq.-output o outputs the frequency corresponding to zero flow.
• Flow reading on display o0
• Totalizer reading o the totalizers are pegged at the last correct value.
Deactivation of the pressure shock suppression
The pressure shock suppression is deactivated after the time interval, set in this function,
has passed (see point b in graphic).
! Note!
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).
A0001285-en
m = Off-value (low flow cut off)
n = On-VALUE (low flow cut off)
a Active when value falls below the on-value of the low flow cut off
b Deactivated after specified time expires
c Flow values are again used to calculate the pulses
■ Suppressed values
QFlow
Function description
BASIC FUNCTION o PROCESS PARAMETER o CONFIGURATION
n
m
a
b
c
inactive
active
inactive
t
Pressure shock suppression
Command:
Valve closes
Q
Given time
After filling
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