Frequency Converter Operation; Instructions For Maintenance - Elektror ND series Betriebs- Und Montageanleitung

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4.2 Frequency converter operation

A frequency converter is used, allowing a wide range of
speed adjustments. There is only a small, load-related dif-
ference in rpm between idle state and the max. load of the
blowers and the lateral channel blower.
To ensure trouble-free operation of blowers and lateral
channel blowers, it is important that the converter meet
the following requirements:
• Converter output equal to or greater than motor power
output *))
• Converter current equal to or greater than motor current *)
• Converter output voltage equal to rated motor voltage
• Versorgungsspannung max. 480V
(inklusive +5% Spannungstoleranz)
• The pulse frequency of the converter should be 8 kHz,
because a lower pulse frequency will lead to noisy motor
operation
• The values for the maximum/minimum frequency can be
found at „1.11 Speeds".
• The converter should have a connection for a tempera-
ture sensor (PTC resistor sensor) or a temperature switch
(normally-closed contact)
*) Refer to the rating plate for data
The motor can be operated in a delta or star-point confi gu-
ration, depending on the input voltage of the converter.
The following U/f assignments must be confi gured at
the converter.
U
B
0
f and U = refer to rating plate
B B
If this is ignored, the motor current will increase dispropor-
tionately and the drive motor will fail to achieve its rated
speed.
Warning!
To avoid personal damage, destruction of the
blower or motor overload, a higher frequency
(speed) than the frequency (f
rating plate must never be set on the converter
otherwise the motor may be overloaded or the
blower destroyed due to the increased speed. The
temperature sensors are connected to the corre-
sponding converter inputs to protective the drive
motor. Single-phase alternating current motors
are not suitable for converter operation.
It is absolutely essential that you observe the
installation and safety instructions described in
the respective operating or application manuals
provided by the frequency converter supplier to
guarantee a safe and trouble-free operation.
It is also important to note that special ambient
conditions may lead to a high level of contamina-
tion of the cooling fi ns with the FUK devices. The
frequency converter switches off if the cool-
ing output on the cooling fi ns is not adequate.
Regular cleaning is required for devices in these
environments.
Prohibited
range
f
B
) specifi ed on the
B
Operating and assembly instructions ND
Note!
The following times apply for the respective
device motor output class (see rating plate) with
run-up/expiry as well as speed changes in order
to to avoid high component loads and faults in
the converter operation:
Device motor output
Motor output < 0.25 kW
0.25 kW < Motor output
<=3.0 kW
3.1 kW < Motor output
<= 7.5 kW
7,6 kW < Motor output
<= 11.0 kW
11,1 kW < Motor output
<= 30.0 kW
A uniform run-up and expiry must be guaranteed within the
run-up and expiry times.
No speed changes must occur during operation that exceed
the speed change during run-up and expiry.
Protection by residual-current-operated circuit breaker
(FI circuit-breaker):
The present IGBT frequency converters produce discharge
currents of >=3.5 mA due to their design principle. These dis-
charge currents can lead to unwanted tripping in systems
protected by a 30 mA-FI circuit-breaker.
If a fault occurs, fault currents can also discharge through the
PE conductor as direct current. If protection is needed on the
supply side by means of an FI circuit-breaker, then an ACDC
sensitive (type B) FI circuit-breaker must be used. Use of an
FI circuit-breaker other than type B can cause death or seri-
ous injury if a fault occurs. To meet the EN 61800-5-1 stand-
ard, the PE conductor must be duplexed and routed through
separate terminals or have a cross-section of at least 10 mm²
Cu.
Operation and connection to public grids:
See "3.5 Declaration concerning the EMC Directive"
4.3 Hydraulic Motor Operation
The run-up and expiry times as well as the speed changes
specifi ed in "4.2 Frequency converter operation" should be
noted when operating with hydraulic motors. Free-running
hydraulic motors should be used to guarantee a smooth run
on.
5 INSTRUCTIONS FOR MAINTE-
NANCE
Wearing parts are subject to the recommended maintenance
intervals (refer to "5.1 Ball bearings" to "5.4 Cleaning"). The
service life of wearing parts (ball bearings and fi lters) de-
pends on the operating hours, the load and other infl uences,
such as temperature, etc.
Maintenance and servicing may only be performed by per-
sons with the necessary expertise and regular training. In ad-
dition to the appliance's operating instructions and the regu-
lations and recommendations for the system as a whole, the
following points should be observed:
Inspection and maintenance intervals:
The operator must set the cleaning, inspection and mainte-
nance intervals himself according to operating hours, load
and operating conditions.
Run-up time Expiry time
[s] [s]
5 10
10 20
20 40
30 60
30 100
EN
15