CONTROL PANEL OPERATING MANUAL AIR COOLED SCROLL CHILLER & HEAT PUMP MICROTECH III CONTROLLER Software Version 3.01.A D-EOMHP00607-14EN Table of Content Introduction ........................................................................................................................................... 5 1.1 Controller Features ............................................................................................................................ 6 2 System Outline ............................................................................................................................... 7 2.1 Communication components ............................................................................................................. 7 2.2 Unit I/O Mapping................................................................................................................................ 7 2.3 Unit Mode .......................................................................................................................................... 9 3 Unit Functions ................................................................................................................................ 9 3.1 HEAT, the Unit Mode ......................................................................................................................... 9 3.2 HEAT / COOL w/GLYCOL the Unit Mode ............................................................................................ 9 3.3 HEAT / ICE w/GLYCOL the Unit Mode ................................................................................................ 9 3.4 Calculations ........................................................................................................................................ 9 3.4.1 Evaporator Delta T ...................................................................................................................... 9 3.4.2 LWT Slope ................................................................................................................................. 10 3.4.3 Pull-down Rate.......................................................................................................................... 10 3.4.4 LWT Error .................................................................................................................................. 10 3.4.5 Unit Capacity ............................................................................................................................. 10 3.4.6 Control Band ............................................................................................................................. 10 3.4.7 Staging Temperatures ............................................................................................................... 10 3.5 Unit States ........................................................................................................................................ 11 3.6 Unit Status ........................................................................................................................................ 11 3.7 Power Up Start Delay ....................................................................................................................... 12 3.8 Evaporator Pump Control................................................................................................................. 12 3.9 Evaporator Pump configuration ....................................................................................................... 13 3.9.1 Primary/Standby Pump Staging ................................................................................................ 13 3.9.2 Auto Control ............................................................................................................................. 13 3.10 LWT Target ....................................................................................................................................... 13 3.10.1 Leaving Water Temperature (LWT) Reset ................................................................................ 13 3.10.2 Leaving Water Temperature (LWT) Override ........................................................................... 14 3.10.3 4-20mA Reset ........................................................................................................................... 14 3.10.4 OAT Reset ................................................................................................................................. 14 3.11 Unit Capacity Control ....................................................................................................................... 15 3.11.1 Compressor Staging in Cool Mode ........................................................................................... 15 3.11.2 Compressor Staging in Heat Mode ........................................................................................... 15 3.11.3 Compressors Staging Delay ...................................................................................................... 15 D-EOMHP00607-14EN - 1/66 3.11.4 Demand Limit............................................................................................................................ 16 3.11.5 Network Limit ........................................................................................................................... 17 3.11.6 Maximum LWT Pull down/up Rate ........................................................................................... 18 3.11.7 High Ambient Limit ................................................................................................................... 18 3.11.8 Fan Control in “V” configuration .............................................................................................. 18 3.12 Evaporator Target ............................................................................................................................ 19 3.12.1 Unbalanced load management ................................................................................................ 19 3.12.2 Staging Up ................................................................................................................................. 19 3.12.3 Staging Down ............................................................................................................................ 19 3.12.4 VFD ............................................................................................................................................ 20 3.12.5 VFD State .................................................................................................................................. 20 3.12.6 Stage Up Compensation ........................................................................................................... 20 4 Circuit Functions ........................................................................................................................... 20 4.1 Calculations ...................................................................................................................................... 20 4.1.1 Refrigerant Saturated Temperature ......................................................................................... 20 4.1.2 Evaporator Approach ................................................................................................................ 20 4.1.3 Condenser Approach ................................................................................................................ 20 4.1.4 Suction Superheat..................................................................................................................... 20 4.1.5 Pump-down Pressure ............................................................................................................... 21 4.2 Circuit Control Logic ......................................................................................................................... 21 4.2.1 Circuit Enabling ......................................................................................................................... 21 4.2.2 Circuit States ............................................................................................................................. 21 4.3 Circuit Status .................................................................................................................................... 22 Pump-down Procedure................................................................................................................................ 22 4.4 Compressor Control ......................................................................................................................... 22 4.4.1 Compressor Availability ............................................................................................................ 23 4.4.2 Starting a Compressor .............................................................................................................. 23 4.4.3 Stopping a Compressor ............................................................................................................. 23 4.4.4 Cycle Timers .............................................................................................................................. 23 4.5 Fan Control in “W” configuration ..................................................................................................... 23 4.5.1 Fan Staging ...............................................................................................................................