Midea LSBLG MCF Series User Manual

MCAC-CTSM-2018-1 Flooded type water cooled screw chiller (MIC)
57
Time relay use Omron H3Y type.
3) Compressor and fan thermal overload relay
Thermal overload relay takes advantage of heating effect to protect the compressor and fans.
Compressor thermal relay value:
The calculation of compressor overload value (transformation ratio of current mutual inductor is A/B) is as
follows:
(Maximum running current of compressor/current mutual inductor A) x B = Thermal relay value of compressor
For example, if the maximum running current of compressor is 250 A, and the transformation ratio of current
mutual inductor is 300/5, Thermal relay value = (250/300) x 5 = 4.17
Note: Use a value that is smaller than the calculated one. For example, in the preceding calculation, the calculated
value is 4.17; in practice, set the value to 4.15.
Unit Type
Maximum Running
Current of Compressor
Transformation Ratio of
Current Transformer
Thermal Relay Value of
Compressor
340
141.4
200/5
3.5
440
169.4
250/5
3.3
540
206.1
300/5
3.4
720
241.2
400/5
3.5
805
331.7
500/5
3.3
890
366.8
600/5
3.0
1055
203.0x2
300/5
3.3
1200
277.4x2
300/5
3.8
1300
281.2x2
400/5
3.5
1410
281.2x2
400/5
3.5
1620
331.7x2
500/5
3.3
1780
366.8x2
500/5
3.0
T： 6S
Power LED
On display red
Time’s up LED
Up display green
TEST key: to press to test whether the
overload relay is normal in stop condition
Reset key: to press to reset the overload
relay if there is compressor overload
protection
Current setting panel: to set the
protection current value.
Note：Compressor overload relay, only apply to 3UA series of Siemens brand

Midea LSBLG MCF Series Specifications

General

Brand	Midea
Model	LSBLG MCF Series
Category	Chiller
Language	English