Voltage Output Units; Current Output Units; Calibration - Setra Systems 230 Installation Manual

3.1 Voltage Output Units

The Model 230 is a 3-wire circuit with three terminals available for wiring.
The - Excitation and - Output are commoned on the circuit.
Input Power
The 230 can operate from either 9-30 VDC for 0-5 VDC output version or
13-30 VDC for 0-10 VDC output version.
Excitation
COM
OUT

3.2 Current Output Units

Model 230 (current output) transducers are true 2-wire, 4-20 mA current
output devices and deliver rated current into any external load of 0-1000 ohms.
The 4-20 mA current output units are designed to have current flow in one
direction only. PLEASE OBSERVE POLARITY.
We suggest that any electrical cable shield be connected to the system's
loop circuit ground to improve electrical noise rejection.
MIN Supply Voltage:
MAX Supply Voltage:

4.0 CALIBRATION

The 230 transducer is factory calibrated and should require no field adjustment.
Whenever possible, any zero and/or span offsets should be corrected by
software adjustment in the user's control system. However, zero and span
adjustments are made by removing the cover on the top of the 230 and the
6-32 seal screws in the plastic terminal block. Be sure to reinstall seal screws
after zero and/or span adjustments. Current output transducers (4-20 mA)
are factory calibrated using a 250 ohm load at 24 VDC. Zero and span adjust
ments are approximately 300 mV (for voltage units) and ± 1.0 mA (for current
units), individually.
The 230 Series is calibrated with the diaphragm in the vertical position
(pressure ports horizontal). For use in other orientations, position the unit and
adjust the zero by following the calibration procedure in the previous section.
Connected to positive terminal of DC Power Supply
Connect as the reference for power supply and output signal
Connect to positive terminal of Control or Pressure Monitor
9 + .02 x (Resistance of receiver plus line)
30 + .004 x (Resistance of receiver plus line)
+
+
Power Supp
—
Setra
Transmitter
(4-20 mA)
—
+
—
Load
(Monito
4