Danfoss vlt aqua Design Guide

Switching frequency
When adjustable frequency drives are used together with sine-wave filters to reduce the acoustic noise from a motor, the switching frequency must be
set according to the sine-wave filter instructions in par. 14-01
Switching Frequency .
Aluminum conductors
Aluminum conductors are not recommended. Terminals can accept aluminum conductors, but the conductor surface has to be clean, oxidation must be
removed, and the area must be sealed by neutral acid-free Vaseline grease before the conductor is connected.
Furthermore, the terminal screw must be retightened after two days due to the softness of the aluminum. It is crucial to keep the connection a gas-tight
joint, otherwise the aluminum surface will oxidize again.
5.3.7 Fuses
NOTE!
All fuses mentioned are max. fuse sizes.
Branch circuit protection:
In order to protect the installation against electrical and fire hazards, all branch circuits in an installation - the switch gear, machines, etc. - must be
protected from both short circuit and overcurrent in accordance with national/international regulations.
Short circuit protection:
The adjustable frequency drive must be protected against short circuit in order to prevent electrical or fire hazard. Danfoss recommends using the fuses
mentioned in tables 5.3 and 5.4 to protect service personnel or other equipment in case of an internal failure in the unit. The adjustable frequency drive
provides full short circuit protection in case of a short circuit in the motor output.
Overcurrent protection:
Provide overload protection to avoid fire hazard due to overheating of the cables in the installation. Overcurrent protection must always be provided in
accordance with national regulations. The adjustable frequency drive is equipped with internal overcurrent protection that can be used for upstream
overload protection (UL applications excluded). See par. 4-18. Fuses must be designed for protection in a circuit capable of supplying a maximum of
100,000 A
rms
(symmetrical), 500 V/600 V maximum.
Non UL compliance:
If UL/cUL is not to be complied with, Danfoss recommends using the fuses mentioned in table 5.2, which will ensure compliance with EN50178:
In case of malfunction, not following the recommendation may result in unnecessary damage to the adjustable frequency drive.
5 How to Install VLT
®
AQUA Drive Design Guide
5-20 MG.20.N5.22 - VLT
®
is a registered Danfoss trademark
5

Danfoss vlt aqua Specifications

General

Supply Voltage	200-240V, 380-500V, 525-600V
Enclosure	IP20
Features	Energy optimization
Approvals	CE, UL, cUL
Input Voltage Range	200-240V, 380-500V, 525-600V
Output Voltage Range	0 to supply voltage
Protection Features	Overvoltage, Undervoltage, Overcurrent, Short circuit, Ground fault
Communication Interfaces	PROFIBUS
Cooling Method	Air-cooled