Terminal Connections; Cable And Earth / Ground Connection - Honeywell Series 3000 MkII Technical Manual

SERIES 3000 MKII TECHNICAL MANUAL

6.3 Terminal connections

All electrical connections are made at the terminal module. To access the terminal module follow the
procedure below:
1. Remove the detector's cover by unscrewing it in a counter-clockwise direction.
2. Remove the display module by pulling it firmly away from the enclosure without twisting it.
Internal Earth/
Ground Connection
Display Module
Plug in Socket
Note: Nominal tightening
torque of 6.9lb-in. to be
applied to the terminal
clamping screws.

6.4 Cable and earth / ground connection

Between the Controller and Transmitter use 2 core (plus screen 90% coverage), suitably mechanically
protected copper cable with a suitable M20 explosion-proof gland, or ¾ in. NPT steel conduit, with 0.5
to 2.0mm2 (equivalent approx. 20 to 14AWG) conductors. Ensure the cable gland is installed correctly
and fully tightened.
To ensure good EMC/RFI immunity bond the system to ground / earth as shown in the diagram below.
Controller Controller
Notes:
• No two 'Earth Points' should be connected via screen and / or conduit so as to avoid 'ground loops'.
(Except between the sensor and transmitter which is a digital link).
• Where multiple 'Earth Points' are unavoidable (e.g. transmitter mounted on metal superstructure
which is earthed then screen and / or conduit to controller should be isolated appropriately).
• ' Bonded Points' (continuity of screen) may be achieved using appropriate glands / cable or conduit;
internal and external 'Earth Points' in the transmitter are provided.
Transmitter Transmitter
Bonded Point Bonded Point
Earth Point Earth Point
S3KMKIIMAN_MAN0878_Issue 6_01/2014
Terminal
number
1
2
Cable Screen Cable Screen
Metal Conduit Metal Conduit
13
Conduit/Cable Entry
Supplementary
External Earth/
Ground Connection
Detector Controller
Terminal Connection
+ +VE
- Signal
Sensor Sensor
Or Or