Yokogawa EXA PH202 2-Wire pH/ORP Analyzer - Manual (Page 22)

IM 12B07D02-01E
Specification 2-9
2-6. Control Drawing of PH202S mA HART® Specification (FM Intrinsically safe design)
Sensor(s)
terminals 11-17
Max. cablelength: 60 mtr.
Cable dia. : 3…12 mm.
Sensor(s)
terminals 11-17
Max. cablelength: 60 mtr.
Cable dia.: 3…12 mm.
Ùnclassified Location
FM Approved
Power Supply
(HART compatible)
Output
Supply
+
_
G
Classified Location Unclassified Location
+
_
G
Functional
earth
Functional
earth
Intrinsically safe design
FM Class I, Div.1, Group ABCD,
T4 for ambient temp. < 55°C
T6 for ambient temp. < 40°C
PH202S transmitter
+
-
Load
Resistance
Classified Location
Functional
earth
+
_
24 volts DC Nominal
Supply Voltage.
FM Approved safety barrier or
power supply
with Rint = 300
:
(HART compatible)
For electrical data:
see text below.
For electrical data:
see text below.
Intrinsically safe design
FM Class I, Div.1, Group ABCD,
T4 for ambient temp. < 55°C
T6 for ambient temp. < 40°C
PH202S transmitter
Figure 1
Figure 2
・ Electrical data of the PH202S.
-Supply circuit (terminals + and -):
Maximum input voltage Vmax = 31.5 V. Maximum input current Imax = 100 mA.
Maximum input power Pmax = 1.2 W.
Effective internal capacitance Ci = 22 nF. Effective internal inductance Li = 35 PH.
- Sensor input circuit (terminals 11 through 17):
Maximum output voltage Vt = 14.4 V. Maximum output current It = 32.3 mA.
Maximum allowed external capacitance Ca = 600 nF.
Maximum allowed external inductance La = 34 mH
・ If Hand Held Terminal (HHT) is not connected to the power supply lines of the PH202S
(see figure 1):
Any FM Approved barrier or power supply may be used that meets the following requirements.
Voc or Vt d 31.5 V ; Isc or It d 100 mA; Ca t 22nF + Ccable ; La t 35PH + Lcable
If HHT is connected to the power supply lines of the PH202S (see figure 2):
The Hand Held Terminal must be FM Approved. Refer to the manufacturers control drawing of
the HHT and the barrier/power supply to determine the cable parameters.
(Voc or Vt ) + VHHT d 31.5 V; (Isc or It ) + IHHT d 100 mA;
Ca t 22nF + Ccable+ CHHT ; La t 35PH + Lcable+ LHHT
When installing this equipment, follow the manufacturer’s installation drawing.
Installation should be in accordance with ANSI/ISA RP 12.06.01 “Installation of Intrinsically Safe
Systems for Hazardous (Classified) Locations” and the National Electrical Code (ANSI/NFPA 70).
Control equipment connected to the barrier/power supply must not use or generate more than
250 Vrms or Vdc.
・ Resistance between Intrinsically Safe Ground and earth ground must be less than 1.0 Ohm.
・ In case of using cable glands in Outdoor location, they shall be UV rated or made of metal.
WARNING
- Substitution of components may impair Intrinsic Safety
- To prevent ignition of flammable or combustible atmospheres, disconnect power before servicing
or read, understand and adhere to the manufacturer’s’live maintenance procedures.
Application Doc. No.: IKE024-A10 P.4-1 to P.4-2