Fisher & Paykel MR480 Humidifier User Manual


 
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Ref. 185040646 *MR730/720/700/480 Technical Manual ¯ Revision F ¯ Issued March 2001
4.0 CIRCUIT OPERATION.........................................................................................................................9
4.1 Introduction......................................................................................................................................................................................9
4.2 Control Board..................................................................................................................................................................................9
4.2.1 Control Thermistors ......................................................................................................................................................... 9
4.2.2 Input Analog Switches U8 and U9................................................................................................................................ 9
4.2.3 Analog to Digital Converter U10 b,d,e.......................................................................................................................... 9
4.2.4 Processor Control U3....................................................................................................................................................... 9
4.2.5 Power Line Interrupt (Revisions D/F PCBs)............................................................................................................... 10
4.2.6 Power Line Interrupt (Revision H PCB and later)...................................................................................................... 10
4.2.7 41 °C Comparator............................................................................................................................................................ 10
4.2.8 Heaterplate Overtemperature........................................................................................................................................ 10
4.2.9 Watch Dog...................................................................................................................................................................... 10
4.3 Power Board...................................................................................................................................................................................11
4.3.1 Revision D/F PCBs ......................................................................................................................................................... 11
4.3.2 Revision H AND J PCBs ............................................................................................................................................... 11
4.4 Probe Temperature versus Thermistor Resistance...............................................................................................................11
5.0 CALIBRATION ....................................................................................................................................12
5.1 Introduction....................................................................................................................................................................................12
5.2 Equipment Required......................................................................................................................................................................12
5.3 Calibration Procedure for Models with Revision D PCBs or earlier..................................................................................12
5.4 Calibration Procedure for Models with Revision F PCBs or later......................................................................................12
6.0 PERFORMANCE CHECK ..................................................................................................................14
6.1 Introduction....................................................................................................................................................................................14
6.2 Performance Check MR730/720/700......................................................................................................................................14
6.2.1 Equipment Setup Notes:................................................................................................................................................ 14
6.2.2 Setup ................................................................................................................................................................................ 14
6.2.3 Temperature Control Check MR700/720/730.............................................................................................................. 14
6.2.4 Alarms check MR700/720/730 ...................................................................................................................................... 15
6.3 Performance Check (MR480)....................................................................................................................................................15
6.3.1 Equipment Required....................................................................................................................................................... 15
6.3.2 Setup ................................................................................................................................................................................ 15
6.3.3 Temperature Control Check (MR480).......................................................................................................................... 15
6.3.4 Alarms check - MR480................................................................................................................................................... 16
6.4 Dual Probe Temperature Test....................................................................................................................................................16
6.4.1 Equipment Required....................................................................................................................................................... 16
6.4.2 Test Procedure................................................................................................................................................................ 16
7.0 SERVICING INFORMATION............................................................................................................17
7.1 Introduction....................................................................................................................................................................................17
7.2 Printed Circuit Board Removal..................................................................................................................................................17
7.2.1 Control PCB..................................................................................................................................................................... 17
7.2.2 Power PCB....................................................................................................................................................................... 17
7.3 COMPATABILITY.......................................................................................................................................................................17
7.3.1 Hardware compatability................................................................................................................................................. 17
7.3.2 MR480 Transformers ..................................................................................................................................................... 18
7.3.3 Software compatability.................................................................................................................................................. 18
7.4 Heaterplate .....................................................................................................................................................................................18
7.4.1 Heaterplates with screw-in standoffs.......................................................................................................................... 19
7.5 Fault Location................................................................................................................................................................................19
7.6 Screw Torque Settings.................................................................................................................................................................19