Granville-Phillips Mini-Convectron 275 Series, Инструкция по установке, эксплуатации и обслуживанию

Страница: 49 / 52

Service
Mini-Convectron
®
Module with DeviceNet
®
Digital Interface 41
6. If any of the resistance values in Table 6-1 are not within specification,
the gauge tube should be replaced.
7. Phone customer service at 1–303–652–4400 or 1–800–776–6543 to
order a new gauge tube.
8. Hold the PC board/gauge tube assembly and carefully push the end of
the replacement gauge tube into the tube socket until it stops.
Make sure the PC boards are properly mounted in the front and rear
cover slots.
9. Install the side, front and rear cover plates on the PC board/gauge tube
assembly.
10. Install the eight end plate screws.
11. Connect the Trip Point and DeviceNet cable connectors.
Gauge tube failures are most frequently caused by one of the following
conditions:
• Chemical Etching – exposure to fluorine, chlorine or mercury causes
the sensor wire to become chemically etched and damaged.
• Overpower – if the gauge electronics and gauge tube are connected
while the gauge electronics are powered ON and the gauge tube is at
vacuum, a spike in the bridge voltage can occur at initial contact and
damage the sensor wire. Always turn power OFF or unplug the gauge
tube before plugging the gauge into the gauge electronics.
• Shock – extreme shock, such as dropping a gauge, can cause a weld
to fail.