Danfoss VLT Series Service Manual page 142

Pin Schematic Function
No. Acronym
13 DBGATE Brake IGBT gate
pulse train.
(Signal to brake
IGBT.)
14 BRT_ON Brake IGBT 5V
logic level signal.
(Indicates
voltage across
brake IGBT.)
15 OTFLT Temperature /
Voltage out of
range
16 FAN_TST Control signal for
fans
17 FAN_ON Pulse train to
gate SCR's for
fan voltage
control. In sync
with line freq.
18 HI_LOW Control signal
from Power Card
19 SCR_DIS Control signal for
SCR front end
20 INV_DIS Control signal
from Power Card
21 RFI_RL2 Control signal for
RFI
22 UINVEX Bus Voltage
scaled down
23 VDD +24 VDC power
supply
24 VCC +5.0 VDC
regulated supply.
+4.75-5.25 VDC
8-4 VLT is a registered Danfoss trademark
Description
Varies w/ brake duty cycle
Varies w/ brake duty cycle
Monitors Brake resistor, Heatsink temp, Ambient temp, power
supplies voltages.
Indicates Fan Test switch is activated to force the fans on high
7 trigger pulses at 3Khz
Signal to switch fan speeds between high and low
Indicates SCR front end is enabled or disabled.
Disables IGBT gate voltages
Ground signal to enable RFI HF capacitors
Signal proportional to UDC
Yellow LED indicates voltage is present.
Green LED indicates voltage is present.
Reading Using a Digital
Volt Meter
Voltage drops to zero
when brake is turned off.
Voltage increases to
4.04 VDC as brake duty
cycle reaches max.
5.10 VDC level with the
brake turned off.
Voltage decreases to
zero as brake duty cycle
reaches max.
5VDC – No fault
0VDC – Fault
+5VDC – disabled
0VDC – fans on high
5VDC - fans off
~4.3VDC – fans on
+5VDC = fans on high,
Otherwise 0VDC.
0.6 to 0.8 VDC – SCRs
enabled
0VDC – SCR disabled
5VDC – inverter
disabled
0VDC – inverter enabled
24VDC – no RFI
0VDC – RFI enabled
380- 500 V
1VDC = 262 VDC
525 – 690 V
1VDC = 373 VDC
OV switch must be off.
+24 VDC regulated
supply
+23 to 25 VDC
+5.0 VDC regulated
supply +4.75 to 5.25
VDC