5.2.1 General characteristics ............................................................................................................ 33 5.2.2 Electrical symbol ...................................................................................................................... 33 5.2.3 Checking for efficiency............................................................................................................. 33 5.3 Door safety interlock (traditional version) ........................................................................................
34 5.3.1 General characteristics ............................................................................................................ 34 5.3.2 Electrical symbol ...................................................................................................................... 34 5.3.3 Circuit diagrams ....................................................................................................................... 34 5.3.4 Checking for efficiency.............................................................................................................
35 5.4 Instantaneous door safety interlock................................................................................................. 35 5.4.1 General characteristics ............................................................................................................ 35 5.4.2 Operating principle...................................................................................................................
35 5.4.2.1 "Door open" conditions.......................................................................................................36 5.4.2.2 Automatic release device ...................................................................................................36 5.4.2.3 Protective cut-out for solenoid valve ..................................................................................36 5.4.3 Electrical symbol ...................................................................................................................... 36 5.4.4 Circuit diagram .........................................................................................................................
36 5.5 Solenoid valve.................................................................................................................................. 37 5.5.1 General characteristics ............................................................................................................ 37 5.5.2 Electrical symbol ...................................................................................................................... 37 5.5.3 Checking for efficiency.............................................................................................................
37 5.6 Pressure switch................................................................................................................................ 38 5.6.1 General characteristics ............................................................................................................ 38 5.6.2 Pressure switch hydraulic circuit..............................................................................................38 5.6.3 Operating principle...................................................................................................................
39 5.6.4 Electrical symbol ...................................................................................................................... 39 5.6.5 Circuit diagram ......................................................................................................................... 39 5.6.6 Checking for efficiency............................................................................................................. 39 5.7 Analogue (electronic) pressure switch.............................................................................................
40 5.7.1 General characteristics ............................................................................................................ 40 5.7.2 Operating principle................................................................................................................... 40 5.7.3 Electrical symbol ...................................................................................................................... 41 5.7.4 Circuit diagrams and operating frequency ...............................................................................
41 5.7.5 Checking for efficiency............................................................................................................. 41 5.8 Commutator motor........................................................................................................................... 42 5.8.1 General characteristics ............................................................................................................ 42 5.8.2 Operating principle...................................................................................................................
42 5.8.2.1 Control of the speed of the motor.......................................................................................43 5.8.2.2 Direction of motor rotation..................................................................................................43 5.8.2.3 Tachometric generator .......................................................................................................44 5.8.3 Electrical symbols .................................................................................................................... 44 5.8.4 Circuit diagram .........................................................................................................................
45 5.8.5 Checking for efficiency............................................................................................................. 45 5.9 Induction motors (asynchronous) .................................................................................................... 46 5.9.1 General characteristics ............................................................................................................ 46 5.9.2 Operating principle...................................................................................................................
46 5.9.3 Checking the efficiency ............................................................................................................ 46 5.10 Inverter (if featured) ......................................................................................................................... 47 5.11 Heating element............................................................................................................................... 48 5.11.1 General characteristics ............................................................................................................
48 5.11.2 Electrical symbol ...................................................................................................................... 48 5.11.3 Checking for efficiency............................................................................................................. 48 5.12 NTC temperature sensor (incorporated in the heating element)..................................................... 49 5.12.1 General characteristics ............................................................................................................
49 5.12.2 Electrical symbol ...................................................................................................................... 49 5.12.3 Checking for efficiency............................................................................................................. 49 5.13 Drain pump ...................................................................................................................................... 50 5.13.1 General characteristics ............................................................................................................
50 5.13.2 Electrical symbol ...................................................................................................................... 50 5.13.3 Checking for efficiency............................................................................................................. 50 5.14 Water control (if featured) ................................................................................................................ 51 5.15 Circulation pump (if featured) ..........................................................................................................
52 5.15.1 General characteristics ............................................................................................................ 52 5.15.2 Electrical symbol ...................................................................................................................... 52 5.15.3 Checking for efficiency............................................................................................................. 52 5.16 Circuit diagrams............................................................................................................................... 53 SOI/DT 2006-03 dmm 4/70 599 37 67-82