ADB Safegate IDM 8000, User Manual

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3.0 Introduction
This manual includes installation, operation, maintenance and troubleshooting information for the IDM 8000 Constant
Current Regulator (CCR).
3.1 General
3.1.1 IDM 8000
IDM 8000 is a microprocessor based CCR designed specifically for supplying airfield lighting serial circuits.
3.1.2 Airfield lighting serial circuit (AFL-circuit)
Serial circuit is normally used at airports for power transmission from the CCR to rather remote located and power consuming
light fittings. Light fittings are connected via isolation transformers to a serial loop fed by the CCR. The output current of the
CCR which defines the brilliancy of the light fittings is kept constant at each current step against supply, load and
environmental changes. Current steps are provided in order to adjust the light output of the system to match with prevailing
meteorological conditions.
Power of the circuits normally varies up to 30kVa which means the max output current being always 6.6A that high output
voltages must be used with larger CCRs. Normally all components (e.g. isolation transformers, connectors etc.) connected to
series circuits are designed for 5kV Rms – voltage.
In short the use of serial circuits and CCRs give the following benefits and disadvantages:
+ Provides equal brightness for all lamps due equal current in the serial loop.
+ Enables low cabling costs and transmission losses due rather low current level (6.6A).
- Because of high voltage used with larger CCRs extra precaution must be used when working with circuits. Regular
maintenance is also needed to maintain proper isolation levels.
3.1.3 Airfield lighting power circuit (AFL-circuit) design guidelines
•
Input power of the CCR is approx. 1.1 x rating of the CCR which should be considered when designing mains supply and
supply cable sizes for the CCR.
•
Mains supply Rsce, min=175 for all CCR sizes (according to IEC 61000-3-4)
•
Output primary cable losses are approx. 160W / km (6.6A / 6mm2 Cu).
•
Output secondary cable losses can be significant and should be calculated according the lengths, diameters and materials
of the cables. Normally isolation transformer can tolerate up to 10% losses without reducing its output current.
•
Isolation transformers efficiencies are normally 0.9 or better which should be taken in account together with the two
above points when defining CCR rating for a circuit.
3.1.4 Specifications
IDM 8000 is designed and manufactured in accordance with following specifications:
ICAO: Aerodrome design manual, Part 5
FAA: AC 150/5345-10E
CENELEC: Pr ENV 50231
IEC: 61822 Edition 1
IDM 8000 has also many unique new features not yet described in public specifications.
UM_IDM-8000, Rev. 1.7, 2021/05/06 9
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