Setra System Model 227 - Manual (Page 3)

Setra
Transducer
(4-20mA)
Power
Supply
Load
(Monitor)
+
+
_
+
_ _
Diagram 4
3
Current must flow in one direction only - Please observe polarity. (See Diagram 4) We
suggest the cable shield Drain Wire be connected to the system’s loop circuit ground
for optimum electrical noise reduction. On transducers with integral connectors (e.g.,
on Bayonet, or D-sub connector types), connection to transducer case ground can be
achieved by connecting the cable drain/shield wire to the mating cable-mounted
connector shell (see Note 1)
Note 1: The transducer case and integral Bayonet Connector shell, D-sub
Connector Shell, and Mini Din shell clips are electrically connected.
Note 2: ETL Listed to UL1604 Standards:The current output unit (excluding units
ordered with the Mini Din Shell) may be installed in UL1604 Class 1 Hazardous
(Classified) Group A, B, C, D, Division 2 locations if the unit is ordered for these
locations. (This is denoted by an N1 designation in the Part Number, 12th and
13th digits.) Safety barriers are not required as long as the unit is operated
under normal conditions with a maximum excitation voltage of 30 VDC
between the input terminals.
Note 3: ATEX 94/9/EC Approved: Special hazardous area instructions for 227 transduc-
ers (with the N1 suffix) with ATEX approval: The 227 transducer (with the N1
suffix) is designed for use in hazardous areas indoor applications with ATEX
rating: Non-incendive II 3G Eex nL IIC T4 X -30
°C<Ta<+80°C. (Note: Units
ordered with the Mini Din Shell are not ATEX approved for use in hazardous
locations.)
• The device can only be used for “Indoor Applications”.
• Power must be turned off before connecting or disconnecting.
• For the connector version, the connector must be secured before applying
power and DO NOT SEPARATE WHEN ENERGIZED.
• The shielded cable must be used and the drain wire of the cable must be
connected to the earth ground. The drain wire of the cable must connect to
the connector metal outer shell for the connector version.
• The maximum allowable transient disturbance must not exceed more than
40% of the maximum excitation voltage.
4.0 CALIBRATION
The 227 transducer is factory calibrated to the specific input pressure
range vs. output voltage or current and should require no field adjust-
ment. For absolute pressure ranges, the zero can be adjusted with full
vacuum applied to the pressure port. For compound ranges, the zero