Azbil JTD720A, User Manual, Page: 51 / 76

Azbil Corporation Instrument maintenance and troubleshooting
Model JTD720A - Smart Multivariable Transmitter 4-1
Chapter 4 : Instrument maintenance and
troubleshooting
This chapter describes this device’s data storage, assembly and disassembly, output
checking, calibration methods, and countermeasures if problems occur.
4-1 : Assembly and Disassembly of this Device
4-1-1 : Cautions During Assembly and Disassembly
Warning
When detaching this product from the process for maintenance and
the like, clear vents and drains in order to remove residual pressure and
residues in the measurement target. In addition, when clearing vents and
drains, check the direction in which material will come out in order to
avoid any contact with the human body. There is a danger of scalding
and other harmful health effects. If the measured fluid is harmful to the
human body, take safety measures such as wearing goggles or a mask so
that it does not adhere to the skin or the eyes, become inhaled, etc.
Particular care must be exercised due to the fact that, for pressure-
resistant, explosion-proof transmitters, the pressure-resistant, explosion-
proof performance specifications may be lost as a result of corrosion,
deformation, or scratching of the case or case cover, or damage to the
threaded portions or connecting surfaces.
Do not open the case cover in the hazardous areas described in 4-1-2
when the device is powered up.
For pressure-resistant, explosion-proof model transmitters, the pressure-
resistant, explosion-proof performance specifications are ensured by
locking the case cover. Fasten the case cover completely, and be sure to
lock it.
Replace damaged seal gaskets. If this product is operated in a damaged
state, it will not be possible to ensure sufficient performance of the seals, and
there is a danger that the measured fluid will spurt out, possibly resulting in
scalding and other harmful health effects.
Use genuine parts as replacements. In particular, for gaskets, adapter
flanges, and the like, parts from other manufactures may in some cases
fit into place, but they cannot ensure pressure resistance and airtightness.
The result may be leakage of the measured fluid, with possible harmful
effects on human health.
Be sufficiently careful of residues from measured fluids which are left
behind in the product. If materials which affect the human body are
contained in these residues, harmful effects on human health could result.
When performing maintenance on a product which has been uninstalled,
first clean the pressure-receiving parts adequately.
If evidence of corrosion is observed in pressure-bearing parts such as
through bolts, nuts, and pressure-release rings, replace them. Parts whose
pressure-resistance has decreased can break and thus are dangerous.
There is also a risk of physical injuries such as bruises and lacerations
caused by broken parts.
When loosening through bolts and nuts to remove the device, hold
the drain ring assembly to prevent it from falling off. If it falls because
sufficient care is not taken, it can cause injuries or product damage.