Danfoss VLT AutomationDrive FC 301 Programming Manual page 10

Introduction
1 1
WARNING
DISCHARGE TIME
The frequency converter contains DC-link capacitors,
which can remain charged even when the frequency
converter is not powered. High voltage can be present
even when the warning LED indicator lights are off.
Failure to wait the specified time after power has been
removed before performing service or repair work can
result in death or serious injury.
•
Stop the motor.
•
Disconnect AC mains and remote DC-link power
supplies, including battery back-ups, UPS, and
DC-link connections to other frequency
converters.
•
Disconnect or lock PM motor.
•
Wait for the capacitors to discharge fully. The
minimum waiting time is specified in Table 1.3
and is also visible on the product label on top
of the frequency converter.
•
Before performing any service or repair work,
use an appropriate voltage measuring device to
make sure that the capacitors are fully
discharged.
Voltage [V]
200–240
380–500
525–600
525–690
Table 1.3 Discharge Time
NOTICE
When using Safe Torque Off, always follow the
instructions in VLT
Off Operating Instructions.
NOTICE
Control signals from, or internally within, the frequency
converter may in rare cases be activated in error, be
delayed, or fail to occur entirely. When used in situations
where safety is critical, for example when controlling the
electromagnetic brake function of a hoist application, do
not rely on these control signals exclusively.
8
VLT
Minimum waiting time (minutes)
4 7
0.25–3.7 kW –
(0.34–5 hp)
0.25–7.5 kW –
(0.34–10 hp)
0.75–7.5 kW –
(1–10 hp)
– 1.5–7.5 kW
(2–10 hp)
®
Frequency Converters - Safe Torque
Danfoss A/S © 10/2019 All rights reserved.
®
AutomationDrive FC 301/302
NOTICE
Hazardous situations must be identified by the machine
builder/integrator who is responsible for considering the
necessary preventive means. More monitoring and
protective devices may be included, always according to
valid national safety regulations, for example law on
mechanical tools and regulations for the prevention of
accidents.
Crane, lifts, and hoists
The controlling of external brakes must always have a
redundant system. The frequency converter can in no
circumstances be the primary safety circuit. Comply with
relevant standards, for example:
Hoists and cranes: IEC 60204-32.
Lifts: EN 81.
Protection mode
Once a hardware limit on motor current or DC-link voltage
is exceeded, the frequency converter enters protection
mode. Protection mode means a change of the PWM
modulation strategy and a low switching frequency to
minimize losses. This continues for 10 s after the last fault
and increases the reliability and the robustness of the
frequency converter while re-establishing full control of the
motor.
In hoist applications, protection mode is not usable
because the frequency converter is unable to leave this
mode again and therefore it extends the time before
15 activating the brake, which is not recommended.
Protection mode can be disabled by setting
5.5–37 kW
parameter 14-26 Trip Delay at Inverter Fault to 0, which
(7.5–50 hp)
means that the frequency converter trips immediately if 1
11–75 kW
of the hardware limits is exceeded.
(15–100 hp)
NOTICE
11–75 kW
(15–100 hp)
Disabling protection mode in hoisting applications
11–75 kW
(parameter 14-26 Trip Delay at Inverter Fault = 0) is
(15–100 hp)
recommended.
M0013101