Installation and Operation Manual
EP Series Pro
-B
loc
®
IPDE-IOM-EP-SERIES-PROBLOC
Page
6
of 10
ECO-0364767
Rev: -
The secondary and vent are then closed (the primary valves is already closed) and the instrument safely
removed.
The double block gives two isolations to prevent process escape while the instrument is removed. Once
the instrument is calibrated or replaced with a new one it can be fitted back on top of the valve outlet
and the primary and secondary valves opened again to allow pressure measurement to continue.
It is possible to calibrate a pressure transmitter without removing it; this is in situation calibration
commonly called “in-situ” calibration. To do this you follow the above procedure to vent the valve. Then
a known pressure is pumped into the open vent, a handheld device is then connected to the back of
the transmitter with electrical leads after removing the cover. If the known pressure from the pump
agrees with the electrical reading from the transmitter it is in calibration and the measuring equipment
removed, then the valves are returned to their operating positions.
If however the readings do not agree, the measuring device has the ability to electronically change the
reading to make it agree with the known pressure, this is done by turning a
k
nob clockwise or anti
