Inverter Operation; Maximum Operating Current - Models 4Mtl-35 To 4Mtl-50; Recommendations For Use With An Inverter - Emerson Copeland 4MTL-05 Series Application Manuallines

5.7

Inverter operation

Stream compressors are released for inverter applications with inverters from Control Techniques or
other brands available on the market.
Compressor Nominal power
4MSL-03
4MSL-04
4MSL-06
4MSL-08
4MSL-12
4MSL-15
4MTL-05
4MTL-07
4MTL-09
4MTL-12
4MTL-15
4MTL-30
4MTL-35
4MTL-40
4MTL-50
Table 15: Inverter operation – Approved frequency ranges
NOTE: The frequency range depends on the operating conditions. For approved application
envelope please contact Application Engineering or refer to Copeland Select software at
www.climate.emerson.com/en-gb.
5.7.1 Maximum Operating Current – Models 4MTL-35 to 4MTL-50
Large Stream CO compressors from 35 to 50 hp have a different MOC in operation with frequency
2
drives. Table 16 below shows the values for both types of operation.
Compressor MOC (A)
4MTL-35 59.6
4MTL-40 67.4
4MTL-50 82.7
Table 16: Maximum operating current for large Stream CO

5.7.2 Recommendations for use with an inverter

Running the Stream CO
resonances might occur in the lower f requency ranges. This phenomenon strongly depends on the
system design and operating conditions.
Emerson conducted extensive tests to investigate compressor behaviour in terms of resonances.
The testing indicates that the f ollowing hardware variables have a significant impact on possible
resonances:
▪ Mounting parts: The rubber mounting parts supplied with Stream compressors are suitable for
the whole f requency range from 25 to 70 Hz.
▪ Piping design: It is recommended to pay particular attention to the discharge line design. A
discharge pipe parallel to the compressor axis normally gives a positive ef fect to reduce
resonances at low frequencies.
▪ Base frame design: The framework structure should be stiff enough to ensure that its resonance
f requencies are above the maximum 70 Hz f requency. A design with natural f requencies below
the minimum 25 Hz speed may lead to high vibrations during start-up.
NOTE: Performance data and envelopes are published in Copeland Select software available
at www.climate.emerson.com/en-gb.
34
Displacement
3
m /h @ 50 Hz
3 hp 4.6
4 hp 6.2
6 hp 7.4
8 hp 9.5
12 hp 12.5
15 hp 17.9
5 hp 4.6
7 hp 6.2
9 hp 7.4
12 hp 9.5
15 hp 12.5
30 hp 17.9
35 hp 22.7
40 hp 26.6
50 hp 32.0
MOC (A)
VS
67.1
75.8
90.6
compressor with an inverter is a reliable application. Nevertheless
2
Approved
frequency
ranges
25 - 70 Hz
25 - 70 Hz
30 - 70 Hz
25 - 70 Hz
30 - 70 Hz
(check approved
application
envelope)
compressors
2
AGL_Stream_ST_4MTL_4MSL_EN_Rev02
Recommended
mounting parts
Hard rubber kit
# 3189744