
Document: LT0273
MX4428 MXP Engineering / Technical Manual
Issue 1.5
24 March 2006
Page v
3.25.2
SAD .............................................................................................................................. 3-51
3.25.3
AVF/SAD ...................................................................................................................... 3-51
3.25.4
FLOWSWITCH ............................................................................................................. 3-51
CHAPTER 4 ANALOGUE LOOP DESIGN CONSIDERATIONS ...........................4-1
4.1
ANALOGUE LOOP CONFIGURATION SELECTION .......................................................... 4-2
4.1.1
LINES & LOOPS ............................................................................................................ 4-2
4.1.2
LOOP FAULT TOLERANCE .......................................................................................... 4-2
4.1.3
AS1670.1 DESIGN REQUIREMENTS........................................................................... 4-2
4.1.4
NZS4512 DESIGN REQUIREMENTS ........................................................................... 4-2
4.2
ANALOGUE LOOP/LINE LAYOUTS .................................................................................... 4-3
4.2.1
LINE MODE .................................................................................................................... 4-3
4.2.2
LOOP DESIGN WITH SHORT CIRCUIT ISOLATORS.................................................. 4-3
4.2.3
STAR CONNECTION OF ANALOGUE LINES .............................................................. 4-5
4.2.4
SPURS ........................................................................................................................... 4-5
4.3
CABLE SELECTION CONSIDERATIONS............................................................................ 4-6
4.4
AC REQUIREMENTS ............................................................................................................ 4-7
4.4.1
GENERAL....................................................................................................................... 4-7
4.5
DC CONSIDERATIONS......................................................................................................... 4-7
4.5.1
GENERAL....................................................................................................................... 4-7
4.6
MECHANICAL CONSIDERATIONS ..................................................................................... 4-7
4.7
NOISE CONSIDERATIONS .................................................................................................. 4-8
CHAPTER 5 MXP CURRENT CONSUMPTION .....................................................5-1
5.1
THEORY ................................................................................................................................ 5-2
5.1.1
ALARM CURRENT......................................................................................................... 5-2
5.1.2
QUIESCENT CURRENT ................................................................................................ 5-3
5.1.3
HEAT LOSS.................................................................................................................... 5-3
CHAPTER 6 EVENT LOG AND STATUS AT MX4428 ..........................................6-1
6.1
RETURNED ANALOG VALUES ........................................................................................... 6-2
6.2
FAULT AND ALARM EVENT LOG....................................................................................... 6-3
CHAPTER 7 MXP TECHNICAL DESCRIPTION ....................................................7-1
7.1
GENERAL.............................................................................................................................. 7-2
7.2
CIRCUIT DESCRIPTION ....................................................................................................... 7-3
7.2.1
BLOCK DIAGRAM.......................................................................................................... 7-3
7.2.2
MICROPROCESSOR & LOGIC CIRCUITRY ................................................................ 7-3
7.2.3
MXP POWER SUPPLY .................................................................................................. 7-4
7.2.4
MX4428 LOOP INTERFACE.......................................................................................... 7-6
7.2.5
ANALOGUE LOOP INTERFACE ................................................................................... 7-7
7.3
MXP ADJUSTMENTS.......................................................................................................... 7-10
7.3.1
40V ISO SUPPLY VOLTAGE ADJUSTMENT ............................................................. 7-10
7.3.2
TX DATA VOLTAGE ADJUSTMENT ........................................................................... 7-10
7.3.3
40V ISO SUPPLY CURRENT LIMIT ADJUSTMENT................................................... 7-10
7.4
MXP LED INDICATIONS ..................................................................................................... 7-11
7.5
PARTS LIST ........................................................................................................................ 7-12
CHAPTER 8 MXP DIAGNOSTIC TERMINAL ........................................................8-1
8.1
MXP DIAGNOSTIC TERMINAL OPERATION...................................................................... 8-2
8.1.1
INTRODUCTION ............................................................................................................ 8-2
8.1.2
MENU OF COMMANDS................................................................................................. 8-2
8.1.3
SELECTING POINTS FOR MONITORING.................................................................... 8-2
8.1.4
DISPLAYING DEVICE ANALOGUE VALUES - CV, TV, ETC ....................................... 8-3
8.1.5
ST (STATUS COMMAND) ............................................................................................. 8-5
8.1.6
ANALOG LOOP DIAGNOSTICS.................................................................................... 8-6
8.1.7
ADVANCED COMMANDS ............................................................................................. 8-8
8.1.8
MX4428 DIAGNOSTICS ................................................................................................ 8-8