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SR250HL Series - 250 W Power Supply/Float Charger for Lead Acid Ba$eries
The user is responsible for ensuring that input and output wiring segregation complies with local standards and that in the use of the equipment,
access is confined to operators and service personnel. A low resistance earth connection is essential to ensure safety and additionally, satisfactory
EMI suppression (see below).
HAZARDOUS VOLTAGES EXIST WITHIN A POWER SUPPLY ENCLOSURE AND ANY REPAIRS MUST BE CARRIED OUT BY A
QUALIFIED SERVICEPERSON.
Electrical Strength Tests
Components within the power supply responsible for providing the safety barrier between input and output are constructed to provide electrical
isolation as required by the relevant standard. However EMI filtering components could be damaged as result of excessively long high voltage tests
between input, output and ground. Please contact our technicians for advice regarding electric strength tests.
Earth Leakage
Where fitted, EMC suppression circuits cause earth leakage currents which may be to a maximum of 3.5mA.
Ventilation
High operating temperature is a major cause of power supply failures, for example, a 10
o
C rise in the operating temperature of a component will
halve its expected life. Therefore always ensure that there is adequate ventilation for the equipment. Batteries in particular suffer shortened
lifetimes if subjected to high ambient temperatures.
Water / Dust
Every effort must be made in the installation to minimise the risk of ingress of water or dust. Water will almost always cause instant failure. The
effects of dust are slower in causing failure of electronic equipment but all electrical equipment should be cleaned free of any dust accumulation at
regular intervals.
Electromagnetic Interference (EMI)
Switching power supplies and converters inherently generate electrical noise. All wiring should be as short as practicable and segregated from all
equipment wiring which is sensitive to EMI. Residual noise can be reduced by looping DC wiring through ferrite cores (sleeves). These are most
effective as close to the power supply as possible and as many turns of the wire taken through the core (+ and - in the same direction) as the core
will accommodate.
External fuse protection
Fuses or circuit breakers must be used in all battery circuits to protect against short circuits. External fuses should be used for power supplies/
chargers even though they are usually internally protected.
Connection polarity
It is critical to check the polarity carefully when connecting DC devices even with models which have non-destructive reverse polarity protection
.
1. SAFETY
PSU
= power supply unit
BCT
= baDery condiEon test
ECB
= electronic circuit breaker
ELVD
= electronic low voltage disconnect
RPP
= reverse polarity protecEon
EMI
= electromagneEc interference
Glossary of terms used in our user manuals
SNMP
= Simple Network Management
Protocol
EMC
= ElectromagneEc compaEbility
DOD
= depth of discharge
