Metek RCT 10 series, Инструкция по установке и эксплуатации

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Installation
11
Integral units are pre-wired at the factory. Figure 2-7
shows the wiring of the integral unit.
For remote units, the signal connections are made to the
four-terminal block on the front of the chassis. Due to
the low power consumption of the instrument, the wiring
need only be light gauge (e.g. 20 AWG). Twisted shielded
pair cables are recommended for lengths over 200 feet.
The cable from the sensing element is connected to the
five-terminal strip on the back side of the instrument
chassis. The cable connections are probe (
prb
) or center
wire (
cw
), ground (
gnd
), and shield (
shd
). See Figure 2-8
for wiring connections of the remote unit.
Only coaxial cables supplied by Drexelbrook should be
used to connect the transmitter to the sensing element.
Use of other cables can result in unstable performance.
2.5 Wiring the Sensing Element
CAUTION !
Before using Intrinsic Safety Barriers, read
manufacturer's instruction for barrier operation.
The 409-T has a built-in current limiter which holds the
signal current to a maximum of 28 mA.
The cable connections to the sensing element are shown
in Figure 2-8
• Do not connect the cable to the sensing element
until after the sensing element has been installed
in the vessel and the condulet housing has been
secured.
• If the sensing element does not have a shield
connection, (the most common condition for a 2-
terminal sensing element) be sure to clip and /or
tape the shield wire at the sensing element
end of the cable only. See Figure 2-8.
Only coaxial cables supplied by Drexelbrook should be
used to connect the transmitter to the sensing element.
Use of other cables can result in unstable performance.
2.4 Wiring the Electronic Unit (Continued)