YOKOGAWA PR20, Руководство пользователя

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IM 12B6K3-E-E
2
1. GENERAL
1-1. Description
The retractable fitting with ball-valve
allows a safe insertion and retrac-
tion of a combined pH/reference
electrode while the process is
under pressure. It can be mounted
in a variety of positions as long as
the electrode is in an almost vertical
position with the tip pointing down-
ward (see fig. 2-1).
The insertion depth can be selected
on site. A minimum insertion depth
of 0.2 mtr. into the process liquid is
advised to have a fast temperature
response. A special 'memory' ring
is provided to remember the posi-
tion of the electrode after retraction.
To protect any loss of process
liquid the mechanism for releasing
the probe is designed to operate
only when the ball-valve is closed.
The combined pH/reference elec-
trode can be replaced or calibrated
easily. The especially designed
cable has integrated leads for the
temperature sensor, shielding and
liquid earth. The end is pre-finished
with cable endings for easy moun-
ting to industrial transmitters.
1-2. Features
- A safe "through the valve" inser-
tion and retraction design.
- Additional safety though a special
designed 'T-bar' locking mecha-
nism.
- Maintenance, replacement and
calibration of the electrode without
interruption of the process.
- Adjustable insertion depth for
optimal measuring position in the
process.
- Easy replacement of the electrode.
- Improved sealing and damping by
addition O-rings.
- Integrated liquid earth and tempe-
rature sensor (Pt100 or Pt1000 to
IEC 751 or DIN 43760).
- Simplified installation by optional
ball-valves with flanged or tapered
connections.
- Available in two different materials
and two different lengths (0.5 mtr.
and 1 mtr.)
1-3. Safety precautions
The PR20 has been designed to
give maximum safety in operation.
For optimum safety a flanged ball-
valve is recommended.
Yokogawa does not accept any
claims or penalties on possible
damages or accidents which occur-
red by operation of the PR20 fitting.
The installation of the probe is to be
implemented under the local safety
regulations for pressurised vessels
or pipe-lines for retraction or inser-
tion. The instructions given in this
manual must be followed exactly.