Danfoss VLT FC 302 User Manual

Problems are possible at start and at low RPM values if
motor sizes vary widely. The relatively high ohmic
resistance in the stator of small motors calls for a higher
voltage at start and at low RPM values.
3.6.3 F-frame Options
Space heaters and thermostat
There are space heaters mounted on the cabinet interior of
F-frame frequency converters. These heaters are controlled
by an automatic thermostat and help control humidity
inside the enclosure. The thermostat default settings turn
on the heaters at 10 °C (50 °F) and turn them off at 15.6
°C (60 °F).
Cabinet light with power outlet
A light mounted on the cabinet interior of F-frame
frequency converters increases visibility during servicing
and maintenance. The housing includes a power outlet for
temporarily powering tools or other devices, available in 2
voltages:
•
230 V, 50 Hz, 2.5 A, CE/ENEC
•
120 V, 60 Hz, 5 A, UL/cUL
Transformer tap set-up
If the cabinet light and outlet and/or the space heaters
and thermostat are installed, transformer T1 requires its
taps to be set to the proper input voltage. A 380-480/500
V frequency converter is initially set to the 525 V tap and a
525-690 V frequency converters is set to the 690 V tap to
ensure no overvoltage of secondary equipment occurs if
the tap is not changed before applying power. See
Table 3.15 to set the proper tap at terminal T1 located in
the rectifier cabinet.
Input voltage range [V] Tap to select [V]
380 V-440 400
441 V-490 460
491 V-550 525
551 V-625 575
626 V-660 660
661 V-690 690
Table 3.15 Transformer Tap Set-up
NAMUR terminals
NAMUR is an international association of automation
technology users in the process industries, primarily
chemical and pharmaceutical industries in Germany.
Selecting this option provides terminals organised and
labeled to the specifications of the NAMUR standard for
frequency converters input and output terminals. This
requires VLT
®
PTC Thermistor Card MCB 112 VLT
®
Extended Relay Card MCB 113.
RCD (Residual Current Device)
Uses the core balance method to monitor ground fault
currents in grounded and high-resistance grounded
systems (TN and TT systems in IEC terminology). There is a
pre-warning (50% of main alarm set-point) and a main
alarm set-point. Associated with each set-point is an SPDT
alarm relay for external use. Requires an external “window-
type” current transformer (supplied and installed by the
customer).
•
Integrated into the frequency converter safe
torque off circuit
•
IEC 60755 Type B device monitors AC, pulsed DC,
and pure DC ground fault currents
•
LED bar graph indicator of the ground fault
current level from 10–100% of the set-point
•
Fault memory
•
TEST/RESET button
Insulation Resistance Monitor (IRM)
Monitors the insulation resistance in ungrounded systems
(IT systems in IEC terminology) between the system phase
conductors and ground. There is an ohmic pre-warning
and a main alarm set-point for the insulation level. An
SPDT alarm relay for external use is associate with each
setpoint.
NOTICE
Only one insulation resistance monitor can be connected
to each ungrounded (IT) system.
•
Integrated into the frequency converter safe
torque off circuit
•
LCD display of the ohmic value of the insulation
resistance
•
Fault memory
•
INFO, TEST, and RESET buttons
IEC emergency stop with Pilz safety relay
Includes a redundant 4-wire emergency-stop push button
mounted on the front of the enclosure and a Pilz relay that
monitors it in conjunction with the frequency converter
STO (safet torque off) circuit and the mains contactor
located in the options cabinet.
Manual motor starters
Provide 3-phase power for electric blowers often required
for larger motors. Power for the starters is provided from
the load side of any supplied contactor, circuit breaker, or
disconnect switch. Power is fused before each motor
starter, and is off when the incoming power to the
frequency converters is off. Up to 2 starters are allowed
(one if a 30 A, fuse-protected circuit is ordered), and are
integrated into the frequency converter STO circuit.
Unit features include:
•
Operation switch (on/off)
•
Short-circuit and overload protection with test
function
•
Manual reset function
Installation
Operating Instructions
36 Danfoss A/S © Rev. 2014-07-29 All rights reserved. MG37A202
33

Danfoss VLT FC 302 Specifications

General

Brand	Danfoss
Model	VLT FC 302
Category	Controller
Language	English