Flowserve 3200MD - Manual (Page 12)

User Instructions - Digital Positioner 3200MD LGENIM0059-09 12/13
12
6 Wiring and Grounding
Guidelines
(See Figure 6)
 WARNING: This product has electrical conduit connec-
tions in either thread sizes ½ " NPT or M20 which appear
identical but are not interchangeable. Housings with
M20 threads are stamped with the letters M20 above
the conduit opening. Forcing dissimilar threads together
will damage equipment, cause personal injury and void
hazardous location certifi cations. Conduit fi ttings must
match equipment housing threads before installation. If
threads do not match, obtain suitable adapters or contact
a Flowserve representative.
6.1 4-20 mA Command Input Wiring
Verify polarity when making fi eld termination connection. The Logix
3200 is reverse polarity protected. Wire 4-20 mA current source to
the input terminal labeled 4-20 mA Input on the user interface board
(See Figure 6). Never connect a voltage source directly across the
Logix 3200MD terminals. The current must always be limited for
4-20 mA operation. Minimum operating current is 3.6 mA.
The input loop current signal to the Logix 3200MD digital positioner
should be in shielded cable. Shields must be tied to a ground at only
one end of the cable to provide a place for environmental electrical
noise to be removed from the cable. In general, shield wire should
be connected at the source.
!
NOTE: The Logix 3200MD positioner carries an intrinsically safe
barrier rating of 100 mA. Input currents should not exceed 100
mA.
6.2 Grounding Screw
The green grounding screw, located inside the termination cap,
should be used to provide the unit with an adequate and reliable
earth ground reference. This ground should be tied to the same
ground as the electrical conduit. Additionally, the electrical conduit
should be earth grounded at both ends of its run.
 WARNING: The green grounding screw must not be used
to terminate signal shield wires.
6.3 Compliance Voltage
(See Figure 7)
Output compliance voltage refers to the voltage limit that can be
provided by the current source. A current loop system consists of
the current source, wiring resistance, barrier resistance (if present),
and the Logix 3200MD positioner impedance. The Logix 3200MD
digital positioner requires that the current loop system allows for
a 10.0 VDC drop across the positioner at maximum loop current.
The 10.0 VDC drop across the Logix 3200MD positioner terminals
is generated by the positioner from the 4-20 mA loop current input.
The actual voltage at the terminals varies from 9.8 to 10.0 VDC
depending on the current mA signal, HART communications, and
ambient temperature.
Figure 6: Field Termination
ANALOG
OUTPUT
HART
4-20 mA INPUT
Shielded Cable
4-20 mA Current Source
Connect Shield at Source
Ground 4-20 mA Current Source
Housing EARTH
Terminal
4-20 mA Feedback
Terminals (Optional)
HART Terminals
Field
Terminators