Emerson Rosemount 5900S Series, Справочное руководство

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3.4 Electrical installation
3.4.1 Cable/conduit entries
The electronics housing has two entries for
½
- 14 NPT. Optional M20
×
1.5, minifast and
eurofast adapters are also available. The connections must be made in accordance with
local or plant electrical codes.
Make sure that unused ports are properly sealed to prevent moisture or other
contamination from entering the terminal block compartment of the electronics housing.
Note
Use the enclosed metal plugs to seal unused ports. The plastic plugs mounted at delivery
are not sufficient as seal!
Note
Thread sealing (PTFE) tape or paste on male threads of conduit is required to provide a
water/dust tight conduit seal and to meet the required degree of ingress protection as
well as to enable future removal of the plug/gland.
NPT is a standard for tapered threads. Engage the gland with 5 to 6 threads. Note that
there will be a number of threads left outside the housing as illustrated below.
Figure 3-19: Cable Entry with NPT Threaded Gland
$
A. The NPT threaded gland leaves a number of threads outside the housing
Ensure that glands for the cable entries meet requirements for IP class 66 and 67.
3.4.2 Grounding
The housing should always be grounded in accordance with national and local electrical
codes. Failure to do so may impair the protection provided by the equipment. The most
effective grounding method is direct connection to earth ground with minimal
impedance. There are three grounding screw connections provided. Two are located
inside the terminal compartment of the housing and the third is located on the housing.
The internal ground screws are identified by a ground symbol: .
Note
Grounding the transmitter via threaded conduit connection may not provide sufficient
ground.
Reference Manual Installation
00809-0100-5900 September 2019
Rosemount 5900S Radar Level Gauge 77