Instruction manual

ControlWave Gas Flow Computer (GFC Plus) Instruction Manual (CI-ControlWave GFC Plus)
Revised Feb-2013 Installation 2-9
2.2.3 Grounding the Housing
The ControlWave GFC Plus enclosure includes a ground lug. See
Figure 2-2 to locate the ground lug. Once you have installed the unit,
run a ground wire (#4 AWG max wire size) between the ground lug and
a known good earth ground. Connect the cases of temperature
transducers, pressure transmitters, and so on to the known good earth
ground. For more information on grounding see the ControlWave
Grounding Supplement (S1400CW):
Additional grounding guidelines include:
 Use stranded copper wire (#4 AWG) to earth ground, and keep the
length as short as possible.
 Clamp or braze the ground wire to the ground bed conductor
(typically a stranded copper AWG 0000 cable installed vertically or
horizontally).
 Using a high-wattage soldering iron, tin the wire ends with solder
before you insert them into the chassis ground lug.
 Run the ground wire so that any routing bend in the cable has a
minimum radius of 12-inches below ground and 8-inches above
ground.
2.2.4 Connecting to the Transducer (MVT or GPT)
Your unit can include either a multi-variable transducer (MVT) or a
gage pressure transducer (GPT).
Within the body of the transducer, metal diaphragms are exposed to the
gas. Solid-state strain gauge sensors in the neck of the transducer
measure the pressure applied to the diaphragms and produce
proportional electrical signals.
The neck of the transducer extends into the bottom of the enclosure,
with the body of the transducer outside the enclosure. The GPT/MVT
cable connector is factory mated with CPU/System Controller Board
connector P1.
Connecting to a Multivariable Transducer (MVT)
Your ControlWave GFC Plus may have an optional multivariable
transducer (MVT) secured to the bottom of the enclosure. The MVT is
factory-connected to connector P1 near the bottom of the CPU/System
Controller board. The MVT pressure assembly connects to the process
manifold either directly or by tubing.
Figure 2-5 details MVT process flange and optional manifold block
connector mounting dimensions.