AMCI NEXUS NX2A4E2, Руководство пользователя

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NX2A4E2 User Manual
I
NSTALLING THE
NX2A4E2
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1.9 Transducer Wiring (continued)
1.9.4 Foreign Dual Resolver Transducers (continued)
In order to ease the installation of Autotech RL210 transducers, the following table can be used to wire one of
theses transducers to an NX2A4E2.
Table T1.1 RL210 Connections to NX2A4E2
1.9.5 Avoiding Ground Loops and Ground Shifts
A ground loop or ground shift can occur when the shields of a cable are attached to earth ground in two
places. A ground loop occurs when the shield can act as a second return path for power currents. A ground
shift occurs when the two places the shield is grounded at are at two different voltage potentials. (The likeli-
hood of a ground shift increases as the cable length increases.) In either case, the shield acts as a low imped-
ance path between the two points which results in a constant current flowing through the shield. To avoid
these problems, the cable shields must not be grounded in two places.

If the shields of the transducer cable are isolated from the body of the transducer, which is the AMCI
standard practice, connect the shields of the transducer cable to the shields of the extension cable and
ground the shields at the NX2A4E2. Treat the shields of the transducer cable as a signal carrying con-
ductors at all junctions and do not connect them to earth ground at any other point. This is the proper
method to wire all transducers attached to the NX2A4E2.

If the shields of the transducer cable are connected to the body of the transducer through an integral
cable but the body of the transducer is isolated from chassis ground by its mounting, connect the shields
of the transducer cable to the shields of the extension cable and ground the shields at the NX2A4E2.
Treat the shields of the transducer cable as a signal carrying conductors and do not connect them to
earth ground at any other point.

If the shields of the transducer cable are connected to the body of the transducer through an integral
cable and the body of the transducer is connected to earth ground by its mounting,
Do Not connect the
shields of the transducer cable to the shields of the extension cable. The shields of the transducer cable
are grounded by the transducer body. Connect the shields of the extension cable to earth ground at the
NX2A4E2. The splice between the transducer and extension cables must be made in a grounded junc-
tion box. You are strongly advised to strip back the cable shields only as far a necessary to make the
splice and keep the wires as short as possible to minimize the possibility of injecting noise into the cable
at the splice.
Function
RL210 Connections
NX2A4E2 Pin
Terminal MS Connector
Coarse/Fine R1 1 A 1
Coarse/Fine R2 2 B 2
Coarse S1 3 C 6
Coarse S3 5 E 4
Coarse S2 4 D 5
Coarse S4 6 F 4
Fine S1 7 H 4
Fine S3 9 L 8
Fine S2 8 K 4
Fine S4 10 M 7
Shields
Do not connect at transducer to avoid
ground loops and shifts
3