Instruction Manual


7-100
IM 01R04B04-00E-E 8th edition March 01, 2011 -00
All Rights Reserved. Copyright © 2003, Rota Yokogawa


Not available if gas measurement
is ordered.
Detection of bubble ow.
After slug criteria has been reached, slug is supervised during slug
duration. If slug is still detected after slug duration has expired, the
selected action in is taken.
See below table.
 Select: 
 To read drive gain.
To set a suitable slug criteria the customer must know the drive gain
level of normal ow condition and of slug ow condition. This function is
suitable to evaluate this level.
 Above this drive gain level slug ow is assumed.
 Duration time is designed to ignore short gas bubbles. Only after Slug
duration has expired the setting in After slug will be taken in account.
In normal slug application set slug duration to zero.
 Select: 
If  is selected mass ow and density keep their value before
occurrence of the slug alarm and as long as slug alarm is detected.
 Set drive gain damping time to get a constant drive gain level.
Gas application?
Yes No
Slug detection off
Slug alarm select = Apply?
Yes No
Drive gain > Slug criteria?
Slug detection off
Yes No
Duration active?
Yes After duration
Function active
Alarm off
Measurement
continued
Slug detection On
Alarm on
Measurement
continued
or value hold
Slug detection off
Alarm off
time
mass flow
drive gain
density
single
bubble
slug flow
duration time
mass flow, if
Hold
mass flow, if
Measured value
T88.EPS
Influence of slug on mass flow, density and drive gain :