User Guide

ZSME000000016
7
EXCELL PRECISI
ON CO., LTD
2.4 Connections
Two terminals are provided, labeled "Field cable” and “Instrument cable”. Field cable is the
independent, exposed cable between the weighbridge and weighing cabin. Instrument or
load cell cable is a locally short connection, such as from SP151 to the junction box,
independent load cell or weighing scale. Equipments connected to the terminal are subject
to SP151 protection.
SP151 allows the 4-wire (SIG1, SIG2, EXC1, EXC2) or line 6 (SIG1, SIG2,EXC1, EXC2,
SENSE1, SENSE2) as well as two isolated lines. The function of each terminal is clearly
marked on the junction box.
The isolated lines connected to field cables and instrumentation cables are not connected
with the ground wire of the SP151 without affecting the ground operation of the general
weighing system.
If your vendor requires the isolated lines to be grounded, it should be connected to
the junction box or load cell.
Cable through the cable seal sleeve, stripped and attached to the corresponding
connections are clearly marked and the subsequent failure detection would be easier.
Ensure that the seal sleeve casing is tight, and then lock the lid.
Figure 4
SP151
Field Cable
(Unprotected)
Inst
rumentation
or Cell Cable
AC Power feed
Weigh Computer
Consumer Unit
Earth/Ground
Connection
*
Subsidiary earth
bond if
earth/ground link
>3m/10ft