Heatsink and Door/Top Fans
14-52 Fan Control
can be used to command the fans to run
at 100% speed.
1.
Use
14-52 Fan Control
to command the fans to
run at 100% speed.
2.
Confirm that the heatsink fan is running by
checking for air flow through the back channel of
the adjustable frequency drive.
3.
Confirm that the door/top fan is running by
checking for air flow around the fan.
The two fans ramp up at different rates, and may take
several seconds, but both will run at 100% speed.
Incorrect Reading
If neither fan is running, the most likely cause is that the
fan control circuit on the power card is faulty. Replace the
power card.
If only one fan is running, the most likely cause is that the
other fan is faulty. Replace the failed fan.
6.4.14 Input Terminal Signal Tests
The presence of signals on either the digital or analog
input terminals of the adjustable frequency drive can be
verified on the adjustable frequency drive display.
16-60 Digital Input
through
16-64 Analog Input 54
display
the status for the standard inputs. Some options add
inputs to the adjustable frequency drive and there are
more parameters to show the status of these inputs.
Digital Inputs
Use
16-60 Digital Input
to display the digital inputs. The
status of control terminals 18, 19, 27, 29, 32, and 33 are
shown left to right with terminal 33 on the right side of
the display. A 1 indicates the presence of a signal, which
means the logic is true and input is on.
Figure 6.12 Digital Inputs Display
If the display does not show the desired signal, the
problem could be the external control wiring to the
adjustable frequency drive, incorrect programming of
5-00 Digital I/O Mode
, or a faulty control card.
Using
5-00 Digital I/O Mode
, the digital inputs can be
programmed to either accept a sourcing output (PNP) or a
sinking output (NPN). When programmed for PNP (factory
default), the digital input turns on when 24 V DC is applied
to the digital input terminal. When programmed for NPN,
the digital input turns on when the terminal is connected
to Signal Common (terminal 20).
The power for the digital inputs can either come from the
(+) 24 V DC built into the adjustable frequency drive, or
from an external power supply. If an external power supply
is used, the common of the supply must be referenced to
terminal 20.
Measure the DC voltage as follows:
1.
Connect the (-) negative meter lead to terminal
20.
2.
Connect the (+) positive meter lead to terminal
12 or 13.
A correct reading is 21–27 V DC. If the power supply
voltage is not present, perform the basic control card
voltage test.
Check the individual inputs if
5-00 Digital I/O Mode
is
“PNP”
Measure the DC voltage as follows:
1.
Connect the (-) negative meter lead to terminal
20.
2.
Connect the (+) positive meter lead to each
digital input in sequence.
The correct display for each digital input where the
voltage reading was greater than 10 V DC is 1. The correct
display for each digital input where the voltage reading
was less than 5 V DC is 0. If the display does not
correspond with the measured inputs, the digital inputs on
the control card have failed. Replace the control card.
Check the individual inputs if
5-00 Digital I/O Mode
is
NPN
Measure the DC voltage as follows:
1.
Connect the (-) negative meter lead to terminal
20.
2.
Connect the (+) positive meter lead to each
digital input in sequence.
The correct display for each digital input where the
voltage reading was less than 14 V DC is 1. The correct
display for each digital input where the voltage reading
was greater than 19 V DC is 0. If the display does not
correspond with the measured inputs, the digital inputs on
the control card have failed. Replace the control card.
Test Procedures
Service Manual
88
Danfoss A/S © Rev. 2014-02-10 All rights reserved.
MG94A222
6
6
Summary of Contents for VLT FC 103
Page 2: ......
