Yamatake Corporation
4-6
ST3000 Smart Transmitter Series 900 Electronic Differential Pressure/Pressure Transmitter
Figure 4-5 Typical Remote DIaphragm Seal Transmitter Installation
ATTENTION
Calculation of Allowable Transmitter Installation Location in Remote Seal Type Dif-
ferential Pressure Transmitter.
When installing a remote seal type differential pressure transmitter on an enclosed
tank, we recommend the installation of the main unit below the lower flange. How-
ever, it is sometimes necessary to install the transmitter main unit between the upper
and lower flanges due to piping restrictions.
The condition that must be satisfied to ensure normal transmitter operations is speci-
fied here.
If a transmitter is installed in the position shown in Figure 4-6, the inner pressure of
the tank (P
0
) and the head pressure of the liquid sealed in the capillary can be applied
to its main unit (low limit flange side).
The transmitter functions normally as long as the pressure applied to its diaphragm
surface is equal to or higher than the low limit P (kPa abs.) of the allowable pressure of
its main unit.
Figure 4-6
100 % Liquid Level
0 % Liquid Level
Fixed
Ref Leg
h
HP
LP
P
0
ρ
¥
100% Level
0% Level