Danfoss VLT HVAC Drive FC 100 Series, Руководство по конструкции

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Figure 2.5 shows a Stopping Category 0 (EN 60204-1) with
safety Category 3 (EN 954-1). The circuit interrupt is caused
by an opening door contact. The figure also shows how to
connect a non-safety related hardware coast.
Control
board
Rectifier
Inverter
Safe
channel
Safety device Cat.3 (Circuit interrupt
device, possibly with release input)
Coast
Short-circuit protected cable
(if not inside installation cabinet)
Door contact
Mains
Frequency
Converter
M
37
5Vdc
12
R
1
R
2
6 phase
130BB566.10
Figure 2.5 Essential aspects of an installation to achieve a Stopping Category 0 (EN 60204-1) with safety Category 3 (EN 954-1).
2.7 Advantages
2.7.1 Why use a Adjustable Frequency Drive for Controlling Fans and Pumps?
A Adjustable frequency drive takes advantage of the fact
that centrifugal fans and pumps follow the laws of propor-
tionality for such fans and pumps. For further information,
see the text and figure
The Laws of Proportionality .
2.7.2 The Clear Advantage - Energy Savings
The very clear advantage of using a Adjustable frequency
drive for controlling the speed of fans or pumps lies in the
electricity savings.
When comparing with alternative control systems and
technologies, a Adjustable frequency drive is the optimum
energy control system for controlling fan and pump
systems.
Figure 2.6 The graph is showing fan curves (A, B and C) for
reduced fan volumes.
Introduction to VLT® HVAC D...
VLT
®
HVAC Drive Design Guide
2-8 MG11BB22 - VLT
®
is a registered Danfoss trademark
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