iZN Series

Brochure (Inverter Drive Ammonia Screw Compressor iZN)

Features

Innovative solution to help decrease global warming:
KOBELCO's inverter drive ammonia screw compressor

Under pressure to reduce global warming, manufacturers are phasing out the use of HCFC as a compressor refrigerant. Even HFC refrigerant, which does not destroy the ozone layer, is designated as a chemical substance subject to emission reduction.

As the disuse of HCFCs moves forward, KOBELCO, which developed the world's first inverter screw compressor, introduces the iZN Series of screw refrigeration compressors.

 

The iZN Series use natural refrigerant NH3 (ammonia), which does not contribute to global warming. KOBELCO's well-established inverter control technology yields energy savings, while accelerating RPM technology. The KOBELCO iZN Series offers not only excellent Coefficient of Performance (COP), but also eco-friendly operation.

Ammonia inverter screw compressor series

Model Name Semi-hermetic type Open type
iZN40W iZN70W iZN80W iZN140W iZN160W iZN200
TUW/A
iZN240
TUW/A
iZN16TX
Ⅱ-5A
iZN20TX
Ⅱ-3A
iZN20TX
Ⅱ-4A
Moter ratings (kW) 24 37 45 37×2 45×2 100 125 135 180 250
Semi-
Hermetic
Condensing
unit
- - - - -
Compressor
unit
- - -
Open Compressor
unit
- - - - - - -

Full loader series

Model Name Open type
SHN20TX
Ⅱ-3A
SHN20TX
Ⅱ-4A
Moter ratings (kW) 220 315
Semi-Hermetic Condensing unit - -
Compressor unit - -
Open Compressor unit
* For the multiple driving system

 

">

Kobelco's six big features.

1. Outstanding energy-saving performance by Kobelco inverter drive compressor

The iZN series can control its cooling capacity with its inverter drive linear speed control to avoid excessive cooling, thereby permitting outstanding energy-saving performance.

A piston valve used for capacity control has been replaced to inverter drive capacity control to ensure optimum operation in accordance with cooling capacity fluctuation.

Outstanding energy saving performance according to partial loading
Saving merit per one year run

2. Maximum 40% increase in cooling capacity by accelerating rotating speed of inverter drive

(Compared with KOBELCO conventional model in 50Hz area)

patent registered No. 3950304 US Patent #6484522

Conventional refrigeration compressor has been unavoidable to reduce cooling capacity significantly accompany with evaporating temperature drops. Accelerating motor speed technology with inverter drive (Patent registered) enable iZN series increase its cooling capacity at lower temperature than -30°C.

The iZN series can perform equally in both of 50Hz and 60Hz area, which is a big merit for 50Hz area users where 20% less performance than 60Hz area has been unavoidable. Those functions enable to select smaller compressor than before.

When suction pressure saturation temperature is -40 cooling capacity is

iZN Series motor speed accelerates accompany with evaporating temperature drop.

Maximum 40% increasable cooling capacity by accelerating rotating speed by inverter drive

3. New iZ monitor with various functions for quick and advance trouble shooting

The New iZ monitor indicates compressor running conditions, various alarms and those histories. It also stops the compressor automatically in an emergency.

  • Alternative running applications
    Alternative linear capacity control or step capacity control can be selected to meet clients' requirements.
  • Suction pressure / Remote temperature capacity control
    Linear capacity control with originally equipped suction pressure sensor and also optionally installed temperature sensor (Supplied by user) at freezing site are available.
  • Additional indication
    Super heat is added to monitor compressor conditions more clearly.
  • Linear capacity control
    Linear capacity control mode enables automatic stepless changing of the rotating speed, with targeted values set for suction pressure and inside temperature.
    Control is possible even with input of a 4-20mA DC signal from the sensor.
  • Step control
    Capacity step control function is also equipped with iZ monitor. Its setting value is available to change flexibly.
New iZ monitor
Compressor protective functions
  • Discharge temperature
  • Oil pressure differential
  • Discharge pressure
  • Over current
  • Motor temperature

4. Merits of motor start-up by inverter drive

Smooth motor startup by inveter drive eliminates inrush current and hot start

The effect of an inverter drive can be found when starting up a compressor, since conventional star-delta start-up induces inrush current and requires an approx 10-minute interval before restarting. Thanks to an inverter that allows smooth starting, the iZN series can restart quickly without any interval. The smooth starting mechanism permits the compressor to stop even when conventional conditions for interruption are not allowed. This mechanism enables more effective energy savings and downsizing of the power facility.

Merits of motor start up by inverter drive

5. Multiple effects created by economizer and inverter drive harmony

The iZN series is equipped with an economizer regulate and control rotating speed at the 1st and 2nd stage of the inverter drive. If the 1st and 2nd stages do not change their rotating speed, economizer cannot perform properly because of pressure unbalance among the 1st , middle and 2nd stages. The iZN series can control rotating speed flexibly and perfectly to supply the best performance.

Multiple effects created by economizer and inverter drive harmony

6. Ammonia resistant motor with aluminum coil

* Semi-hermetic type only

Ammonia resistant motor with aluminum coil

What is a multiple compressor driving system?

A multiple compressor driving system can be implemented when a user needs the full capacity of two or more compressors. In this system, the compressors have similar freezing capacities.

Compressor running priority
  1. Inverter drive model No.1, serving as the capacity controller, starts running.
  2. When the freezing capacity of model No. 1 exceeds 100%, full load model No. 2 starts running.
  3. When the freezing capacities of models No.1 and No. 2 are more than 200%, full load model No. 3 starts running.
Demanded freezing capacity

Compressors No. 2 and No. 3 may start in any order. In other words, after compressor No. 1 reaches full capacity, compressor No. 3 may start first, followed by compressor No. 2.

Compressor Models Capacity Control
Inverter Drive Model 0-100%
Full Load Model 100% only*

* Full Load Model has no capacity control devices with it.

 

Specification

Semi-hermetic type (24 to 125kW motor rating compressor and racks)

Condensing unit standard specifications (-30 to -50°C)

Unit type
Item
iZN40W iZN70W iZN80W iZN140W iZN160W
Frequency 50/60Hz
Refrigerant NH3
Power source Motor: 380V(Other voltages available), 3 phase
Control circuit: 200 to 230V, 1 phase
Number of compressors 1 Unit 2 Units
Capacity control *1*2*3 Continuous control mode or step control mode (3 steps: 50%, 75% and 100%)
Motor Nominal output (kW) 24 37 45 37×2 45×2
Type Water-cooled semi-hermetic induction type
Starting method Inverter
Condenser Type Horizontal shell and tube (serving also as a receiver)
Receiver capacity (ℓ) 46 32 41 144 122
Refrigerant spatial volume (ℓ) 115 129 172 340 305
Connections Refrigerant gas inlet 50A 80A 80A 80A×2 80A×2
Refrigerant liquid outlet 15A 15A 20A 25A 25A
Refrigerant liquid inlet/outlet Condenser Rc2 Rc3 Rc3 100A 100A
Oil cooler Rc1 Rc1 Rc1 Rc1×2 Rc1×2
Motor Rc1 Rc1 Rc1 Rc1×2 Rc1×2
Lubricating oil (ℓ) *4 14 21 29 29 41
Noise dB(A) *5 73 75 75 78 78
Dimensions
W×D×H (mm)
2115×
1135×
1380
2215×
1200×
1445
2235×
1285×
1455
3130×
1910×
1615
3130×
1910×
1615
Weight (kg) 973 1309 1493 2848 3112

Compressor unit standard specifications (-30 to -50°C)

Unit type
Item
iZN40TUW iZN70TUW iZN80TUW iZN140TUW iZN160TUW iZN200TUW/A iZN240TUW/A
Frequency 50/60Hz
Refrigerant NH3
Power source Motor: 380V (Other voltages available), 3 phase
Control circuit: 200 to 230V, 1 phase
Number of compressors 1 Unit 2 Units 1 Unit
Capacity control *1*2*3 Continuous control mode or step control mode (3 steps: 50%, 75% and 100%)
Motor Nominal output (kW) 24 37 45 37×2 45×2 100 125
Type Water-cooled semi-hermetic induction type Refrigerant liquid injection type
Starting method Inverter
Connections Refrigerant gas inlet 50A 80A 80A 80A×2 80A×2 125A 125A
Refrigerant gas outlet 25A 32A 40A 50A 50A 65A 65A
Refrigerant liquid inlet 15A 25A 25A 25A×2 25A×2 25A 25A
Refrigerant liquid outlet 15A 15A 20A 25A 25A 25A 25A
Refrigerant
liquid
inlet/outlet
Oil cooler Rc1 Rc1 Rc1 Rc1×2 Rc1×2 Rc2/25A Rc2/25A
Motor Rc1 Rc1 Rc1 Rc1×2 Rc1×2 - -
Lubricating oil (ℓ) *4 14 21 29 29 41 65 80
Noise dB(A) *5 73 75 75 78 78 86 90
Dimensions
W×D×H (mm)
1485×
1135×
1385
1660×
1190×
1450
1685×
1260×
1450
2684×
2000×
1615
2684×
2000×
1615
2540×
1405/1480×
1640
2605×
1445/1500×
1640
Weight (kg) 822 1038 1136 2500 2700 2393/2406 2509/2522
*1: The minimum capacity depends on products range and operation conditions (25-45%).
*2: Requested to enter proper signal due to selected running mode.
*3: Partial loading value for step control can be flexibly changed.
*4: Oil quantity is minimum charge only for compressor unit. Actual oil quantity for whole of the plant (system) should be determined at the site referring the oil level of sight glasses during compressor running.
Charge oil on site and replenish when the level gets lower than requested. Use specified refrigeration machine oil (Supplied by user).
*5: Noise level (Scale A) indicates the values measured at 1 meter away from the compressor and 1 meter above from the floor level when the suction pressure saturated temperature is -40°C and without any echo influence. In the actual installed conditions the noise level maybe different from indicated value because of the influence of surrounding noise and echo.
* : Noise control and harmonic suppression measurement should be taken as necessary according to respective guidelines.
* : Electric power for control circuit is requested users to supply.

Cooling capacity / Power consumption (kW)

CT
(°C)
ET
(°C)
iZN40W/TUW iZN70W/TUW iZN80W/TUW iZN140W/TUW iZN160W/TUW iZN200TUW/A iZN240TUW/A
Qo
(kW)
Pw
(kW)
Qo
(kW)
Pw
(kW)
Qo
(kW)
Pw
(kW)
Qo
(kW)
Pw
(kW)
Qo
(kW)
Pw
(kW)
Qo
(kW)
Pw
(kW)
Qo
(kW)
Pw
(kW)
35 -30 50.5 26.5 81.7 40.1 97.6 47.9 163.4 80.2 195.2 95.8 220.8 107.2 259.8 126.1
-35 43.1 26.2 70.4 40.0 84.2 47.8 140.8 80.0 168.4 95.6 201.6 107.4 237.2 126.4
-40 35.4 25.7 57.3 39.1 68.7 46.9 114.6 78.2 137.4 93.8 175.1 104.6 206.0 123.1
-45 27.7 24.9 45.0 38.1 53.9 45.6 90.0 76.2 107.8 91.2 135.9 98.3 159.9 115.7
-50 21.0 24.0 34.3 36.8 39.6 42.5 68.6 73.6 79.2 85.0 101.5 88.8 119.4 104.5
40 -30 50.0 28.1 80.9 42.5 96.6 50.7 161.8 85.0 193.2 101.4 218.4 111.5 256.9 131.2
-35 42.4 27.7 69.3 42.3 82.9 50.6 138.6 84.6 165.8 101.2 199.5 112.8 234.8 132.7
-40 34.7 27.2 56.2 41.4 67.3 49.6 112.4 82.8 134.6 99.2 173.2 111.1 203.8 130.7
-45 27.1 26.4 44.1 40.4 52.8 48.3 88.2 80.8 105.6 96.6 134.3 105.1 158.0 123.7
-50 20.6 25.7 33.6 39.4 38.8 45.5 67.2 78.8 77.6 91.0 100.2 95.8 117.9 112.7
* : This is the case for superheat 0°C and economized middle stage evaporative temperature +5°C

Open type

Compressor unit standard specifications (-30 to -50°C)

Unit type
Item
Inverter Drive Model Full Load Model
iZN16TXⅡ-5A iZN20TXⅡ-3A iZN20TXⅡ-4A SHN20TXⅡ-3A SHN20TXⅡ-4A
Frequency 50/60Hz
Refrigerant NH3
Power source Motor: 380V (Other voltages available), 3 phase
Control circuit: 200 to 230V, 2 phase
Number of compressors 1 Unit
Capacity control *1*2*3 Continuous or step control model Full load model
Motor Nominal output (kW) 135 180 250 220 315
Type TEFC Mo. (IP54)
Starting method Inverter Soft starter / Reactor start
(supplied by user)
Connections Refrigerant gas inlet 125A 200A 200A 200A 200A
Refrigerant gas outlet 65A 100A 100A 100A 100A
Refrigerant liquid inlet 20A 25A 25A 25A 25A
Refrigerant liquid outlet 20A 25A 25A 25A 25A
Refrigerant
liquid
inlet/outlet
Oil cooler Rc2 Rc4 Rc4 Rc4 Rc4
Motor - - - - -
Lubricating oil (ℓ) *4 65 140 240 140 240
Noise dB(A) *5 90 88 90 88 90
Dimensions
W×D×H (mm)
3570×1280×1680 4305×1540×2000 4390×1540×2000
Weight (kg) 3485 4400 5375 4500 5500
*1: The minimum capacity depends on products range and operation conditions (25-45%).
*2: Requested to enter proper signal due to selected running mode.
*3: Partial loading value for step control can be flexibly changed.
*4: Oil quantity is minimum charge only for compressor unit. Actual oil quantity for whole of the plant (system) should be determined at the site referring the oil level of sight glasses during compressor running. Charge oil on site and replenish when the level gets lower than requested. Use specified refrigeration machine oil (Supplied by user).
*5: Noise level (Scale A) indicates the values measured at 1 meter away from the compressor and 1 meter above from the floor level when the suction pressure saturated temperature is -40°C and without any echo influence. In the actual installed conditions the noise level maybe different from indicated value because of the influence of surrounding noise and echo.
* : Noise control and harmonic suppression measurement should be taken as necessary according to respective guidelines.
* : Electric power for control circuit is requested users to supply.
* : *1 to 3 of the above are applied only to inverter model.

Cooling capacity / Power consumption / [Shaft] (kW)

CT
(°C)
Pw
(°C)
iZN 16TXⅡ-5A iZN 20TXⅡ-3A iZN 20TXⅡ-4A SHN 20TXⅡ-3A SHN 20TXⅡ-4A
Qo (kW) Pw (kW) Qo (kW) Pw (kW) Qo (kW) Pw (kW) Qo (kW) Pw (kW) Qo (kW) Pw (kW)
35 -30 249.7 113.3 344.9 140.8 516.8 208.9 409.7 167.3 629.0 254.3
-35 231.0 114.3 300.6 141.0 450.2 209.0 324.0 152.0 497.5 231.0
-40 203.7 114.3 251.2 142.1 376.6 210.9 252.0 142.6 387.2 216.9
-45 159.1 102.7 202.4 139.9 303.6 207.7 192.4 133.0 295.6 202.3
-50 118.3 90.0 150.9 132.0 226.5 196.1 143.5 125.4 220.6 191.0
40 -30 246.3 121.8 344.4 153.4 516.0 227.6 409.1 182.3 628.0 277.1
-35 227.2 123.7 299.9 153.3 449.2 227.3 323.3 165.3 496.5 251.2
-40 200.1 123.1 250.5 155.2 375.5 230.4 251.4 155.8 386.1 236.9
-45 156.3 110.9 201.7 153.4 302.5 227.8 191.8 145.8 294.6 221.8
-50 116.0 97.6 150.2 145.6 225.5 216.3 142.8 138.3 219.6 210.6
* : This is the case for superheat 0°C and economized middle stage evaporative temperature +5°C