J DF 3 0 0 |
FI EL D I N D I C ATO R | O I/J D F 3 0 0 - EN R E V. B
9
Securing the housing cover in flameproof areas
The front face of the field indicator housing features a locking
screw (hex-head socket screw) on the top right-end corner
(see picture 5).
•
Install the cover on the housing by hand- tightening it.
• Turn the locking screw counterclockwise to secure the
housing cover. This involves unscrewing the screw until the
screw head stops at the housing cover.
For Hazardous Areas installations, at least six (6) threads on
the cover must be engaged in order to meet flameproof
(explosion-proof) requirements.
Figure 5 Locking screw position
6 Field indicator wiring
Cable connection
Observe the applicable regulations governing electrical
installation. Connections must only be established in a
dead-voltage state. JDF300 field indicator has overvoltage/
lightening according to IEC 61326 (higher capacity must be
provided at the plant). Check that the existing operating
voltage corresponds to the needed voltage.
The same lines are used for both the power supply and output
signal. In case the surge protection option is present and the
field indicator is installed in a Hazardous area, the field
indicator has to be power supplied from a voltage source
isolated from mains (galvanic separation). Furthermore the
potential equalization for the entire powering cable must be
guaranteed since the intrinsic safety circuit of the field
indicator is grounded.
Electrical shock can result in death or serious injury. Avoid
contact with the leads and terminals. High voltage that may be
present on leads can cause electrical shock. Do NOT make
electrical connections unless the electrical code designation
agrees with the classification of the area in which the field
indicator is to be installed. Failure to comply with this warning
can result in fire or explosion.
To remove the LCD, unscrew the housing cover by turning it.
Unplug the LCD by pulling it out gently. On the field indicator
housing there are two connection ports for cable glands or
conduit fittings. These ports are protected with plastic plugs
for transit purpose. The unused port plastic plug must be
replaced for Hazardous Area installations with flameproof
(explosion proof) protection (see relevant warning). Depending
on the design supplied, the electrical connection is established
via cable entry, M20 x 1.5 or 1/2-14 NPT thread. The screw
terminals are suitable for wire cross sections up to 2.5 mm2
(AWG 14).
With Category 3 field indicators for use in “Zone 2”, a
qualified cable gland for this type of protection must be
installed by the customer (see the section “Hazardous Area
Consideration”).
An M20 x 1.5 or 1/2-14 NPT thread is located in the electronics
housing for this purpose. For field indicators with “Flameproof
enclosure” (Ex d) type of protection, the housing cover must be
secured using the locking screw. The screw plug that may have
been supplied with the field indicator must be sealed at the
plant using Molykote DX. The installer assumes responsibility
for any other type of sealing medium used. At this point, we
wish to draw your attention to the fact that increased force will
be required to unscrew the housing cover after an interval of
several weeks. This is not caused by the threads, but instead is
due solely to the type of gasket.
WARNING
IMPORTANT
IMPORTANT
