Zero-Phase Reactors For Reducing Radio Noise (Acls) - Fuji Electric FRENIC-HVAC User Manual

4.4.1.6

Zero-phase reactors for reducing radio noise (ACLs)

An ACL is used to reduce radio frequency noise emitted from the inverter output lines. Pass the total of
four wires--three inverter output wires and a grounding wire through the ACL in the same passing
direction four times. If shielded wires are used, pass them through the ACL with their shields four
times. Be sure to use wires with a heat resistance of 75°C (167°F) or above.
The ACL absorbs high-frequency noise components and emits them as heat into the air so that the
amount of heat generation can be large. If it happens, lower the carrier frequency, upgrade the
heat-resistance rank of wires, increase the number of the ACLs to decrease the number of turns per
ACL, replace the ACLs with higher type ones, or take any other measures.
The wire size is determined depending upon the ACL size (I.D.) and installation requirements. Refer
to Table 6.13.
Figure 4.4-1 Dimensions of Zero-phase Reactor for Reducing Radio Noise (ACL) and Connection Example
ACL type
ACL-40B
ACL-74B
Note: Use wires for the maximum allowable temperature of 75°C (167°F).
Table 6.13 Wire size selection (ACL)
Installation requirements
Number of
Q'ty
turns
1 4
2 2
4 1
1 4
2 2
4 1
4-48
Wire size Wire size
(mm 2 ) (AWG)
5.5 or below 10 or below
14 or below 6 or below
38 or below 1 or below
14 or below 6 or below
60 or below 1/0 or below
250 or below 500 or below