17
4. Specification and Description
4.1 Sensors
Sensor
Type
302S
30HS
312S
312SP
323S
352S
362S
366S
373S
393S
39HS
402S
420S
433S
442S
HL*S
Minimum
Temperature
ºC
-70
0
-70
-70
-70
-70
-210
-210
-70
-70
0
-70
-70
-70
-70
-70
Maximum
Temperature
ºC
150
250
130
130
130
150
65
65
150
150
250
150
150
150
150
130
Maximum
Pressure
Kg/cm2
56
50
21
20
21
56
70
3.5
56
56
50
103
280
105
105
100
Fitting
R¾”
R1½”
R1”
R1”
R¾”
R¾”
R¾”
M6
R¾”
R¾”
R¾”
R¾”
¾” NPT
R¾”
R¾”
Flange
or screw
Frequency
1
1
1
1
1
1
3.75
3.75
1
1
1
3.75
3.75
1.20
3.75
1
Table 4.1 - Sensor specification
* Note that 1 kg/cm2 = 100kPa
4.2 Head Amplifiers
Power supply:
Operating frequency:
Gain:
Output:
Temperature Range:
Test Switches:
Housing:
Cable:
Earthing:
Intrinsic Safety:
Normal 11.5V, 12-16mA from the control unit
1 or 3.7 MHz
Potentiometer adjustable, switchable ranges on MEP**I
Current pulses transmitted to control unit in ‘Normal’ mode (270 Hz)
-25 to 85ºC
Optional: MEP* AI, ***S*PI**, ***S*PM** simulates a break in the sensor cables
(fault test)
MEP*XI simulates active sensor, stopping pulses (alarm test)
i) ***S*PI**: IP54 Aluminium housing, mounted on sensor, Pg 16 cable entries
ii) ***S*PM**: IP68 Gunmetal or Stainless steel, mounted on sensor, M20 cable
entries, holds up to two head amplifier circuits.
iii) MEP*AI: IP65 Polycarbonate, mounted adjacent to sensor
MEP*XI
i) Head amplifier Not supplied, see Section 2.4 (i) for specification.
to control sensor
ii) Sensor to head MEP* (AI, XI) only, supplied with sensors.
amplifier
Head amplifier must not be connected to the screen of the control unit cable.
On adjacent amplifier, the screens of the sensor cables must be connected to the
head amplifier.
Units type MEP3 are intrinsically safe, see table 2.3 for certificate details