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www.basler.com
+1 618.654.2341 (USA)
INTRODUCTION
The Inrush Current Reduction Module (ICRM) prevents
damage to a protected voltage regulator during power-up
by limiting inrush current to a safe level. Without inrush
protection, the inrush current is limited only by the level of
the power source impedance. The lower the impedance,
the greater the risk of damaging the regulator from
excessive inrush current. Devices with a pulse-width
modulated (PWM) power stage are especially vulnerable to
high inrush current due to a large amount of capacitance
inherent to the design. However, voltage regulators that
use SCR-type power stages do not require the protection of
an ICRM since these regulators do not have a large
amount of capacitance in the power stage.
When a voltage regulator with a PWM power stage is
energized, the ICRM limits the inrush current by adding a
high level of resistance in series with the voltage regulator
power input. Once the inrush current subsid es, the series
resistance diminishes quickly to allow nominal, steady-state
current flow.
APPLICATION
Applications where a voltage regulator is powered by a
permanent magnet generator (PMG), auxiliary winding, or
generator output (shunt fed), usually do not require the
protection of an ICRM. These sources usually have a
higher source impedance which inherently minimizes inrush
current. Also, these sources are typically connected directly
to the voltage regulator with no interposing relays,
contactors, or switches. If this is the case, then no inrush
occurs since the source voltage ramps up to its rated value.
However, if rated or near rated voltage is applied to the
voltage regulator, then some amount of inrush current is
expected and an ICRM should be considered. Typically,
voltage regulators in these applications receive power from
a station service bus that is switched by a relay or
contactor. Applications where a PWM type voltage
regulator is powered by a low-impedance source need an
ICRM to minimize the amount of inrush current.
To summarize, if the voltage that powers the voltage
regulator ramps up to nominal as the generator comes up
to rated speed, then an ICRM is not needed. If this is not
the case, an ICRM should be used. If you are unsure
whether your application requires an ICRM, contact Basler
Electric Technical Support Services for assistance.
ICRM Versions
Two versions of the ICRM are available. Each version is
uniquely suited to protect a specific family of Basler Electric
products. Table 1 lists each ICRM model, its part number,
and the compatible products.
Publication
9387900990
Revision
C
Instructions
Part Number
Table 1. ICRM Cross-Reference
ICRM-15 9387900104
If operating power is removed from an energized ICRM,
a minimum interval of five minutes should elapse before
operating power is restored. This cool-down interval
allows the ICRM to regain its ability to limit inrush
current.
AVC63-12, AVC125-10,
SPECIFICATIONS
The following electrical and physical specifications, type
tests, and certifications apply to the ICRM.
Electrical Specifications
Input Voltage: 90 to 277 Vac, 90 to 300 Vdc
Input Frequency: dc, 50 to 420 Hz
Input Current
ICRM-7: 9 Aac
ICRM-15: 18 Aac
Power Dissipation: 25 W
Physical Specifications
Temperature
Operating: –25 to 70°C (–13 to 158°F)
Storage: –40 to 70°C (–40 to 158°F)
Dimensions: Refer to Figure 1
Weight: 227 g (8 oz)
Type Tests
Dielectric
Withstands 2,000 Vac for one minute in accordance with
IEC 60255-5
Shock
Withstands 15 G in three perpendicular planes in
accordance with IEC 60255-21-1
Vibration
Tested in accordance with IEC 60255-21-2. Withstands 2 G
in each of three mutually perpendicular axes, swept over
the range of 10 to 500 Hz for a total of six sweeps, 15
minutes each sweep.
Humidity
Qualified to IEC 68-1, IEC 68-2-28
Certifications
UL Recognition
cURus recognition per UL Standard 508 and CSA Standard
C22.2 No. 14
Date
03/15
Copyright
2015
For terms of service relating to this product and software, see the Commercial Terms of Products and Services document available at www.basler.com/terms.
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CE Qualification
This product meets or exceeds the standards required for
distribution in the Eur ope an co m m unity.
EAC Mark (Eurasian Conformity)
• TP TC 004/2011
• TP TC 020/2011
INSTALLATION
The ICRM may be installed in any environment where the
conditions do not exceed the capabilitie s liste d in the
Specifications section.
Mounting
For maximum cooling, the ICRM should be mounted on a
vertical surface and oriented so that the ventilation holes
are located at the top and bottom of the unit.
Case may become hot during operation.
Figure 1 shows the ICRM mounting dimensions. Mounting
dimensions are identical for both ICRM models.
Dimensions are shown in inches with millimeters in
parenthesis.
Connections
Figure 2 illustrates typical connections for an application
using single-phase operating power. The ICRM is not
phase sensitive. Figure 3 illustrates typical connections for
an application using three-phase operating power.
Table 2 lists the terminal connections for each voltage
regulator that is compatible with the ICRM.
Table 2. ICRM Terminals Cross-Reference
Wiring requirements are subject to the specifications of the
voltage regulator. Refer to the appropriate device
instruction manual for wire sizing, fuse recommendations,
and terminal designations.
TROUBLESHOOTING
The ICRM contains no serviceable component s.
Replacement of the ICRM is recommended in the event of
a failure.
If the protected device is not receiving operating power,
check the following:
• Verify that the ICRM connections between the power
source and voltage regulator are correct.
• Confirm that the voltage supplied by the power source
is sufficient to energize the voltage regulator.
If operating power is applied to the input terminals of the
ICRM but voltage is not present at the output terminals,
remove operating power, disconnect all ICRM wiring, and
perform the following procedure:
1. Connect a suitable ohmmeter across the A-IN and
A-OUT terminals. The resistance measured across the
IN and OUT terminals should be approximately 2 Ω for
the ICRM-7 and 0.5 Ω for the ICRM-15. If an open
circuit or short circuit is detected, the ICRM should be
replaced.
2. Repeat step 1 for the B-IN and B-OUT pair of terminals
and the C-IN and C-OUT pair of terminals.
Voltage Regulator
Publication
9387900990
Revision
C
Instructions
Date
03/15
Page
2 of 4
For terms of service relating to this product and software, see the Commercial Terms of Products and Services document available at www.basler.com/terms.