YOKOGAWA PH450G

<3. Piping and Wiring>
3-7
IM 12B07W01-04EN 1st Edition : Nov. 11, 2016-00
(3) Connection for power supply and ground
<Connection for power supply>
A power supply voltage of 100V AC ±10%, 50/60 Hz is box of the PH8HS3 operating unit of
the chemical cleaning system.
CAUTION
The chemical cleaning pH measuring system has no power switch. To avoid the possible hazard
of electrical shock or damage to the instrument, always install a power switch (double-pole) in the
power line.
Use a two-core cable with an outer diameter of 9 to 12 mm for this connection. Treat both
ends of each core wire of the cable extending from the power supply so they t M4 thread
and then connect them with terminal1 and 2 on the control box. For information on the
distributor power supply, refer to the user’s manual “PH201G Distributor”.
Note Power voltage or connection varies depending on the specication of distributors.
<Connection for ground>
The control box and pH transmitter of the chemical cleaning pH measuring system must
be grounded with a grounding resistance of less than 100Ω. The grounding terminal of
the control box can be found in the bottom of the control box casing. As for the grounding
terminal of the 2-Wire Analyzer, refer to the corresponding instruction manual.
(4) Connection for contact output of CYLINDER FAIL signal
The chemical cleaning system outputs the CYLINDER FAIL contact signal. The contact
signal is output to let the operator know that a failure has occurred in the upward movement
of the pneumatic cylinder of the PH8HS3 holder. The system uses the DETECT UPPER
LIMIT signal discussed in step 2 above for this purpose.
The CYLINDER FAIL contact signal is given when DETECT UPPER LIMIT is not signaled
even if the setting for timer T1 in the control box is reached. This connection is applied
when the above function is used. Follow the same procedure as for the two-wire pH
transmitter system. Use a two-core cable with a nished outer diameter of 9 to 12 mm for
this connection. Treat both ends of each core wire of the cable so they t M4 threads and
then connect terminals 6 and 7 of the control box with the instrument being used, such as an
annunciator.
Note: For the contact capacity and other details, see Subsection 1.1.
(5) Connection for pH signal
To PH201G distributor, 2-Wire Analyzer FLXA202 or FLXA21 sends a 4 to 20 mA output
signal and 2 mAp-p <WASH> signal which is superimposed on the 4 to 20 mA DC signal.
The distributor outputs 1 to 5 V DC signal. Use a double-core shielded cable with a nished
outer diameter of 9 to 12 mm for this connection. For wiring between 2-Wire Analyzer and
the distributor, connect + terminal of 2-Wire Analyzer to terminal A of the distributor, and
connect a minus terminal to terminal B. Shiled of cables must be connected to the ground
terminal G of the 2-Wire Analyzer.
Connect output cables to each corresponding terminal on the distributor or receptor, such as
terminal C, or D. Shield of cables must be grounded on each receptor side.
(6) Connection for contact input of WASH (cleaning) signal
Use a double-core shielded cable with a nished outer diameter of 9 to 12 mm for this
connection. Treat both ends of each core wire of the cable so they t M4 threads and then
connect terminals 4 and 5 of the control box with the distributor terminal e and terminal f.