Contents
1 INTRODUCTION ...................................................................................................... 1
1.1 Overview of Water Level Control ............................................................................................ 1
1.1.1 Water Level Control Philosophy ...................................................................................... 1
1.1.2 Water Level Schematic .................................................................................................... 2
1.2 Water Level Features ............................................................................................................... 3
2 SET-UP ..................................................................................................................... 5
2.1 Expansion Board Wiring and Dimensions ............................................................................... 5
2.1.1 Wiring Diagram ............................................................................................................... 5
2.1.2 Dimensions ....................................................................................................................... 6
2.1.3 Terminals Description ....................................................................................................... 7
2.1.4 Electrical Specification .................................................................................................. 10
2.2 Options ................................................................................................................................. 11
2.3 Commissioning Water Level .................................................................................................. 20
2.3.1 Commissioning Procedure............................................................................................. 20
2.3.2 Operational Checks ...................................................................................................... 23
2.4 First Outs Set-Up ................................................................................................................... 24
2.5 Integrating Other Water Level Controls with Autoflame ....................................................... 26
3 WATER LEVEL PROBES ........................................................................................... 27
3.1 Breaking Bubbles/Spray ....................................................................................................... 27
3.1.1 Thermal Currents (heat energy in water) ...................................................................... 27
3.1.2 Steam Flow Induced Surge ........................................................................................... 28
3.1.3 Foaming ........................................................................................................................ 28
3.2 Schematic Explanation of the Water Level Probe Operation ............................................... 29
3.2.1 Capacitance Probe ....................................................................................................... 30
3.3 Schematic of the Probe Sampling Software .......................................................................... 31
3.4 Capacitance Probe – Externally Mounted Pots .................................................................... 32
3.5 Capacitance Probe – Internally Mounted Pots ..................................................................... 34
3.6 Capacitance Probe – Installation for a Water Tube Boiler ................................................... 36
3.7 External Probe Chamber Dimensions ................................................................................... 37
3.8 Capacitance Probe Specification .......................................................................................... 38
3.8.1 Capacitance Probes Terminals ......................................................................................
38
3.8.2 Water Level Treatment .................................................................................................. 39
3.9 2
nd
Low Probe ........................................................................................................................ 40
3.10 Modulating Feed Water Valve ............................................................................................. 41
3.10.1 Feed Water Valve Exploded Diagram ......................................................................... 41