For FM and CSA approvals, both enclosure of the level switch and pipe
system need to be isolated from each other by using a certified flameproof
seal. The seal must be installed within 18 inches of the enclosure wall.
Unused conduit entries must be sealed using suitably certified blanking
elements (stopping plugs).
3.2.8
Relay and transistor protection
Provide protection for relay contacts and output transistors to protect the
device against inductive load surges.
3.2.9
Static charging
The Rosemount 2521 must be grounded to avoid a static electrical build-up.
This is particularly important for applications with pneumatic conveying and
non-metallic containers.
3.3
Wiring the level switch
Figure 3-1: Connections Overview for Standard and Type 'D' Housings
2
3 4 5
1
B
A
C
A. Internal ground terminal - electronics connected to housing
B. Connection terminals
C. Protective conductor terminal - Protective Earth (PE)
Quick Start Guide
October 2020
18
Quick Start Guide
