Emerson 2468CD User Manual

Page of 186
Hydrastep 2468CB and 2468CD Manual 
2468CB & 2468CD Dual Power Supply Version
 
24685034
 
 
2-3
 
2.1 INTRODUCTION 
This chapter introduces the dual power supply version of the Hydrastep 2468 Electronic 
Gauging System, its mechanical installation, system configuration, simple fault 
analysis/corrective action capability and its specification. 
2.2 
ELECTRODE CABLING SYSTEM 
This system can have 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30 or 32 electrodes and uses 
18-core electrode cables.  The cables consist of nine pairs of coloured cores with the black 
cores in each cable used for the EARTH terminations.  Each electrode requires one pair of 
cores, one core for the signal drive and one for the signal return.
 
Number of 
Electrodes 
Number of Cables 
Required 
10-16 
18-24 
26-32 
3 or 4 
 
The electrode cable is pre-formed for simple installation.  The connections to the electrodes 
are terminated on the connection stud of the electrode.  Either core can be connected to the 
electronic enclosure as the signal drive or return. 
2.3 ELECTRONIC 
ENCLOSURE 
The basic arrangement of boards in the electronic enclosure is as follows: 
 
Two input boards supply power to the system and to the input signal processing 
circuits.  These boards are: PCB 24680501, ac (mains) input, or PCB 24680516, dc 
input.  One board is mounted on the right hand side of the base plate and receives the 
odd numbered electrode inputs.  The other board is mounted on the left hand side of 
the base plate and receives the even numbered electrode inputs. 
 
A display board (PCB 24680515) contains the LED drive circuits for the two columns 
(32 red LEDs and 32 green LEDs) and the system fault LEDs.  This board is mounted 
on the rear of the front panel, with the LEDs protruding through the front panel. 
 
Up to four output boards, Relay Board (PCB 24680504), Relay with time delay Board 
(24680509) or Opto-isolator Board (PCB 24680505) may be fitted, two per input 
board.  Output board mounting pillars are fitted to each input board during 
manufacture to support the first output board mounted. 
Refer to Figure 2.1 on page 2-4 for an annotated view of the internal layout of the unit.