Sierra INNOVA-MASS 241-VTP - Manual (Page 23)

Series 24-HP Instruction Manual Chapter 2 Installation
IM-24-HP 2-9
Flow Meter Insertion
The sensor head must be properly positioned in the pipe. For this reason,
it is important that insertion length calculations are carefully followed. A
sensor probe inserted at the wrong depth in the pipe will result in inaccu-
rate readings.
Insertion flow meters are applicable to pipes 2 inch and larger. For pipe
sizes ten inches and smaller, the centerline of the meter’s sensing head is
located at the pipe’s centerline. For pipe sizes larger than ten inches, the
centerline of the sensing head is located in the pipe’s cross section five
inches from the inner wall of the pipe; i.e., its “wetted” depth from the
wall to the centerline of the sensing head is five inches.
Insertion flow meters are available in three probe lengths:
Standard Probe configuration is used with most flow meter process
connections. The length, S, of the stem is 29.47 inches.
Compact Probe configuration is used with compression fitting process
connections. The length, S, of the stem is 13.1 inches.
12-Inch Extended Probe configuration is used with exceptionally lengthy
flow meter process connections. The length, S, of the stem is 41.47 inch-
es.
Use the Correct Insertion Formula
Depending on your flow meter’s process connection, use the applicable
insertion length formula and installation procedure as follows:
• Flow meters with a compression type connection (NPT or flanged)
follow the instructions beginning on page 2-10.
• Flow meters with a packing gland type connection (NPT or flanged)
configured with an insertion tool, follow the instructions beginning on
page 2-12.
•
Flow meters with a packing gland type connection (NPT or flanged)
without an insertion tool, follow the instructions beginning on page
2-15.
Warning!
An insertion tool must be
used for any installation
where a flow meter is
inserted under pressure
greater than 50 psig.