Mitsubishi Electronics MS-AWA manual

MS-A•W A · MU-A•W A MSZ-A•NA · MUZ-A•NA · MUZ-A•NA - U MSY -A•NA · MUY -A•NA MSZ-FD•NA · MUZ-FD•NA · MUZ-FD•NA - U MSZ-D•NA · MUZ-D•NA · MUZ-D•NA - U MSY -D•NA · MUY -D•NA · MXZ-A•NA SER VICE TECHNICAL GUIDE CONTENTS 1. MS MICROPROCESSOR CONTROL ·················· 4 2. MSZ, MSY MICROPROCES[...]

2 Revision A: • MXZ-3A30NA- 1 has been added. Revision B: • MXZ-2A20NA- 1 , MXZ-4A36NA, MSZ-FD, MSZ-D and MSY -D have been added.[...]

1. MS MICROPROCESSOR CONTROL ··························································· 4 Indoor unit models Outdoor unit models MS-A09W A MU-A09W A MS-A12W A MU-A12W A 1-1. COOL OPERA TION ··················································[...]

4 MS MICROPROCESSOR CONTROL 1 1-1. COOL ( ) OPERA TION MS-A•W A MU-A•W A 2. Indoor fan speed control Indoor fan operates continuously at the set speed by F AN SPEED CONTROL button regardless of the thermostat’s OFF- ON. In AUTO the fan speed is as follows. 1. Thermostat control Thermostat is ON or OFF by difference between room temperature an[...]

5 1. Thermostat control Thermostat is ON or OFF by difference between room temperature and set temperature. 2. Indoor fan speed control Indoor fan operates at the set speed by F AN SPEED CONTROL button. When thermostat OFF (compressor OFF), fan speed becomes V ery Low . In AUTO the fan speed is as follows. 4. Coil frost prevention Coil frost preven[...]

6 1-3. AUTO V ANE OPERA TION 1. Horizontal vane <SWING operation> In swing operation of ECONO COOL operation mode, the initial air flow direction is adjusted to “Horizontal”. According to the temperature of indoor coil thermistor at starting of this operation, next downward blow time is decided. Then when the downward blow has been finish[...]

7 MSZ,MSY MICROPROCESSOR CONTROL 2 2-1. COOL ( ) OPERA TION 2. Indoor fan speed control Indoor fan operates continuously at the set speed by F AN SPEED CONTROL button regardless of the thermostat’s OFF- ON. In AUTO the fan speed is as follows. 1. Thermostat control Thermostat is ON or OFF by difference between room temperature and set temperature[...]

8 Set temperature is as shown on the right chart. The system for dry operation uses the same refrigerant circuit as the cooling circuit. The compressor and the indoor fan are controlled by the room tem- perature. By such controls, indoor flow amounts will be reduced in order to lower humidity without much room temperature decrease. 2-2. DR Y ( ) OP[...]

9 (2) Cold air prevention control MSZ-A09/12/15/17 MSZ-FD MSZ-D When the compressor is not operating, ( ) if the temperature of room temperature thermistor is less than 66 °F , the fan stops. ( ) if the temperature of room temperature thermistor is 66 °F or more and ( ) if the temperature of indoor coil themistor is less than 32 °F , the fan sto[...]

set position set speed set position set speed Indoor fan Compressor normal Outdoor fan R.V . coil (21S4) OFF (COOL) OFF Maximum frequency horizontal Horizontal vane V ery Low (temperature of indoor coil thermistor > 64 °F) 30 seconds 30 seconds 30 seconds 40 seconds 5 seconds 5 seconds 40 seconds OFF OFF OFF ON (HEA T) ON ON ON (HEA T) horizont[...]

11 (2) Mode change In case of the following conditions, the operation mode is changed. COOL mode changes to HEA T mode when 15 minutes have passed with the room temperature 4 °F below the set temperature. HEA T mode changes to COOL mode when 15 minutes have passed with the room temperature 4 °F above the set temperature. In the other cases than t[...]

12 <SWING operation> In swing operation of ECONO COOL operation mode, the initial air flow direction is adjusted to “Horizontal”. According to the temperature of indoor coil thermistor RT12 at starting of this operation, next downward blow time is decided. Then when the downward blow has been finished, next horizontal blow time is decided[...]

13 MUZ-A24 MUY -A24 MUZ-D MUY -D POWER SUPPL Y NOISE FIL TER CIRCUIT RESISTOR RELA Y SMOOTHING CAP ACITOR CURRENT TRANSFORMER COMPRESSOR REACTOR P W V U N IPM PFC U W MS 3~ V + Function of main parts NAME FUNCTION INTELLIGENT POWER MODULE (IPM) It supplies three-phase AC power to compressor . SMOOTHING CAP ACIT OR It stabilizes the DC voltage and s[...]

Input current waveform without P AM Input current waveform with P AM Due to the time of no electricity; · Power factor gets worse. · Harmonic gets increased. Input voltage Energized time is short in case L inductance is small. No electricity runs into diode module because the voltage at both sides of smoothing capacitor is higher than input volta[...]

15 4. Intelligent power module IPM consists of the following components · IGBT (x6) : Converts DC waveform to three-phase AC waveform and outputs it. · Drive Circuit : Drives transistors. · Protection circuit : Protects transistors from overcurrent. Since the above components are all integrated in IPM, IPM has a merit to make the control circuit[...]

16 2-7-3. Sine wave control In these air conditioners, compressor equips brushless DC motor which doesn't have Hall element. In short, the motor is sensorless. However , it's necessary to locate the polar direction of rotor in order to drive brushless DC mo- tor ef fi ciently . The general detection method of the polar direction for such[...]

17 2-8. OPERA TIONAL FREQUENCY CONTROL OF OUTDOOR UNIT 1. Outline The operational frequency is as following: First, the target operational frequency is set based on the difference between the room temperature and the set tem- perature. Second, the target operational frequency is regulated by discharge temperature protection, high pressure protectio[...]

18 2-9. EXP ANSION V AL VE CONTROL (LEV CONTROL) (1) Outline of LEV control The LEV basic control is comprised of setting LEV opening degree to the standard opening °F set for each operational frequency of the compressor . However , when any change in indoor/outdoor temperatures or other factors cause air con- ditioning load fluctuation, the LEV c[...]

19 (2) T ime chart OFF T ime Ti m e ON Operational frequency of the compressor Commanded to open Standard opening degree Opening degree is corrected according to discharge temperature. Positioning Air conditioner ON Air conditioner OFF (thermostat off) LEV opening degree about 5 minutes <COOL, DRY> about 15 minutes <HEA T> (3) Control d[...]

20 (b) Reference value of LEV standard opening degree (pulse) Applied model A B C D E F MUZ-A09/12 COOL 130 190 240 260 260 260 HEA T 100 130 170 210 230 230 MUZ-A15/17 MUY -A15/17 COOL 290 300 350 350 370 370 HEA T 130 150 220 250 280 300 MUZ-A24 MUY -A24 COOL 150 166 186 206 230 260 HEA T 130 150 170 196 210 226 MUZ-FD COOL 180 240 300 320 320 32[...]

21 MXZ MICROPROCESSOR CONTROL 3 3-1. INVERTER SYSTEM CONTROL MXZ-A•NA POWER SUPPL Y NOISE FIL TER CIRCUIT RESISTOR RELA Y SMOOTHING CAP ACITOR CURRENT TRANSFORMER COMPRESSOR REACTOR P W V U N IPM PFC U W MS 3~ V + 3-1-1. Inverter main power supply circuit Function of main parts NAME FUNCTION INTELLIGENT POWER MODULE (IPM) It supplies three-phase [...]

22 3. Power factor improvement Booster coil reactor and PFC rectify AC to DC and control its voltage. In the motor drive system of sine wave control, power factor can be improved by reducing harmonics. PFC and reactor stabi- lize the voltage of DC supplied to inverter circuit and make its waveform smooth. 4. Power transistor module IPM consists of [...]

23 3-2. EXP ANSION V AL VE CONTROL (LEV CONTROL) Linear expansion valve (LEV) is controlled by “Thermostat ON” commands given from each unit. Indoor unit status LEV opening Stop of all indoor unit Opening before stop → 500 pulse in 15 minutes When outdoor unit is operating, some indoor units stop and some operate. COOL : 5 pulse (full closed)[...]

24 In COOL mode, the two indoor coil thermistors (one main and one sub) sense temperature ununiformity (super heat) at the heat exchanger , and when temperature difference have developed, the indoor coil thermistors adjust LEV opening to dimin- ish the super heat. This action is called Evaporation T emperature Protection. Indoor heat exchanger (MXZ[...]

25 23 54 69 84 100 1 15 131 146 38 14 32 41 50 59 68 77 86 MXZ-2A MXZ-3A/4A 23 Compressor operating frequency (Hz) 4Hz 01 02 03 04 05 06 07 08 09 10 LEV Opening (code) Determination of LEV standard opening in each indoor unit • The standard opening is on the straight line, which connects an each standard point in the section where divided into se[...]

26 MXZ-3A30NA- 1 MXZ-4A36NA Exclusive LEV Standard opening (pulse) LEV Opening (code) 123456789 1 0 COOL 126 130 134 138 150 160 170 180 190 200 HEA T 248 248 258 266 274 280 286 292 300 306 Difference in capacity Difference in operation number Code3,4 Code5,6 Code7,8 Code9,10 Code1 1,12 Code13,14 Code15or above 23 4( MXZ-4A ) COOL 3 6 9 12 15 25 3[...]

27 (1) LEV opening correction by discharge temperature The target discharge temperature is determined according to frequency zone and number of operation unit of the com- pressor . <Correction> COOL DRY HEA T Discharge temperature ● 2 ● 2 ● Each correction • (Each gas pipe temperature thermistor - Minimum gas pipe temperature thermist[...]

28 Correct the LEV opening according to the difference between target discharge temperature and discharge temperature. (2) Separate correction (COOL,DR Y) (Correction by the separate super heat) a) Correct the LEV separately by temperature difference between each gas pipe temperature and the minimum gas pipe temperature of all. Calculate each super[...]

29 3-3. OPERA TIONAL FREQUENCY RANGE b) Correct the LEV separately by temperature difference “ ∆ RT” between main/sub indoor coil thermistor . ∆ RT LEV opening correction (pulse) 10.8 ∆ RT 2 7.2 ∆ RT < 10.8 1 ∆ RT < 7.2 1 In addition, decrease the target discharge temperature corresponding ∆ RT . ∆ RT T emperature to be decr[...]

30 3-6. OUTDOOR F AN CONTROL Fan speed is switched according to the number of operating indoor unit and the compressor frequency . 3-5. DISCHARGE TEMPERA TURE PROTECTION CONTROL This protection controls the compressor ON/OFF and operation frequency according to temperature of the discharge tempera- ture thermistor . (1) Compressor ON/OFF When tempe[...]

31 1. Pre-heat control is turned ON for 15 or 30 min, after the breaker is turned ON. 2. 30 min. after the unit is stopped, pre-heat control is turned ON for 15 or 30 min. and turned OFF for 30 min." This is repeated as shown in the graph until the breaker is turned OFF . When outside temperature is 68 °F or below , pre-heat control is ON for[...]

New publication, effective Feb. 2008 Specifications subject to change without notice. Copyright 2006 MITSUBISHI ELECTRIC ENGINEERING CO.,L TD Distributed in Feb. 2008. No. OBT16 REVISED EDITION-B 6 Distributed in May 2007. No. OBT16 REVISED EDITION-A 7 Distributed in Apr . 2006. No. OBT16 7 Made in Japan HEAD OFFICE: TOKYO BLDG.,2-7-3, MARUNOUCHI, [...]