RFI SME240-1 2-20 User manual

SME240-1 2-20
Owner's Manual

Table of Contents
Introduction .................................................................. 1
Safety ............................................................................1
Operating Modes ......................................................... 1
Protection ..................................................................... 2
Battery LVD Operation ................................................ 2
Battery Charging Operational Requirements ................ 3
Battery Temperature Compensation ............................. 3
Thermal Protection ....................................................... 3
Alarm Output ............................................................... 4
Led Indicator ................................................................ 4
Output voltage .............................................................. 4
Dimension & Mounting ................................................. 5
Installation .................................................................... 6
Mounting Options ......................................................... 6
Connectors ................................................................... 6
Alarm/Temperature Sensor ............................................. 6
DC Power Output ........................................................... 6
Connection .................................................................. 7
Cabling ......................................................................... 7
Voltage Setting ............................................................... 7
Cooling ......................................................................... 8
Specifications ............................................................... 8
Approvals ...................................................................... 9
Copyright © RFI 2011
Disclaimer
RFI makes no claim as to the accuracy or suitability of the information contained in this manual or from any other
documentation. RFI accepts no liability for any loss or damage, which may occur as a result of improper or unsafe use of its
products.

READ T IS FIRST!
BEFORE INSTALLING T E SME240-1 2-20 CAREFULLY READ T E FOLLOWING
INSTRUCTIONS, ESPECIALLY T E SAFETY NOTES AND WARRANTY
CONDITIONS.
INTRODUCTION
The RFI SME240-1 2-20 (battery charger/eliminator) provides a power output of 280 watt at
1 3.6 Volts. The nominal input mains may be 220 V to 240 V and 50 z.
The SME240-1 2-20 has been designed specifically for telecommunications applications
demanding high reliability, low noise, fully automatic battery backup, battery protection and full
protection of the output. Many other applications will be able to take advantage of these
features which include:
• Light compact design
• igh Efficiency
• Battery over discharge protection with automatic reset
• igh reliability with conservative thermal design allowing continuous full load operation
with convection cooling
• Alarm for low mains and reverse battery connection
• User accessible output voltage adjustment
• Low noise output, ideal for telecommunications applications
• 3 modes of operation
• Convenient output connector
• Flexible mounting options
• Full protection for the power supply, load and battery
• Local technical support
1
Safety
Correct installation is the most critical factor in ensuring the safe use of the power supply. If
every consideration in the Installation section of this manual has been satisfied the power
supply will be safe to operate.
Operating Modes
The SME240-1 2-20 has three main operating modes:
1 . As a battery eliminator it may be used to power equipment requiring 1 2 V –1 4 V at 20 A. It
is fully protected against overload and short circuit as well as incorporating over voltage
protection.
2. As a lead acid battery charger it will provide safe and convenient method to restore
discharged batteries. Fully charged batteries can be left connected to the unit indefinitely
with no adverse effects on their lifetime.
3. The full features of the unit are realised when both a battery and a load are connected so
that it operates as a power supply with power fail protection. Under normal conditions an
internal switch connects the battery in parallel with the load. The average load must be less
than the capability of the power supply to ensure there is a remainder available to float
charge the battery.

2
When a mains failure occurs, the power supply no longer provides power. The battery
now supports the load without interruption of the load. Restoration of the mains restarts
the power supply which will resume support of the load and charging of the battery.
During extended mains failures the unit disconnects the battery before it becomes
excessively discharged. The battery is automatically reconnected when the mains
recovers. This feature contributes to long battery lifetime and allows unattended operation
of a system.
Protection
The power supply incorporates the following protection features
• Reverse polarity connection of the battery will not cause damage to the power supply or
the battery and the output load will remain unaffected.
• Electronic battery fusing is provided in series with battery connection to protect the load
and power supply when it is powered from the battery.
• Accurate current limit protection is provided for both load and battery. Automatic
recovery from short circuit is provided with no current tailing in short circuit operation.
• Over voltage protection provides shutdown of power supply.
• Inrush Surge limiting at turn on.
• OTP over temperature protection for blocked fuse incorrect install.
Battery LVD Operation
A low voltage disconnect (LVD) is provided to prevent deep discharge of the battery.
LVD Operation
When mains has failed and the battery is supporting the load, the battery must be
disconnected from the load if its voltage falls below the following levels:
Model Battery Disconnect Condition Validation time ±30%
(LVD_Disconnect)
SME240-1 2-20 1 0.25 V ±0.25 V 1 .8 sec
The battery will be connected to the charger/load output when its voltage rises above
the following levels:
Model Battery Connect Condition Validation time ± 30%
(LVD_Reconnect)
SME240-1 2-20 11 .90 ± 0.30 V 2.3 sec
The battery disconnect is incorporated into the Battery +ve line.
The BATTERY output has protection incorporated against a reversed battery connection.
A reversed battery is left disconnected so that the LOAD output can still run the load from
mains power. The quiescent current drain on the battery when the main has failed is less
than 3 mA.

3
Battery Temperature Compensation
When the optional battery temperature sensor TMS1 01 is connected the output voltage will
be adjusted by the amount shown in the table below to maintain the optimal battery
changing voltage.
Temperature Compensation Model Temperature Compensation
(Reference Temperature = 20 °C)
SME240-1 2-20 -1 8 mV/C
Thermal Protection
A thermally controlled fan is used to maintain temperatures a non latching thermal shut
down is used to protect against overheating due to:
• Use in excessive ambient temperature
• Output overload
• Fan failure/blockage
• Other fault conditions
Battery Charging Operational requirements
Trickle Charge
When mains is present but the battery voltage is below the LVD Connect voltage, the
battery is trickle charged circuit that limits the charging current to a trickle charge current
of 1 .0A ± 20%.
Vfloat
During Vfloat mode the battery is charged at 1 0 A until the float voltage is reached.
Vequalise
Periodic equalise at 1 4.25 V is provided for 1 5 minutes every 24 ours.
Battery Charge modes
To maintain the battery in a good state of health a charging algorithm is to be used to
ensure that the correct voltages are applied to the battery terminals at the appropriate
times throughout it’s usage cycle.
The voltages for each Mode at 20°C is:
Float Voltage Equalise Voltage
1 3.65 ± 2% 1 4.05 ± 2%

4
Alarm Output
A pair of normally closed, floating relay contacts are provided to indicate alarm
conditions. Alarm conditions are defined as any one or more of the following events:
• The mains fails.
• Over Voltage shut down has occurred.
• Thermal Shut down has occurred.
• The battery has been connected backwards.
• The battery circuit breaker has tripped.
The relay contacts are rated for 200 mA @ 60 Vdc
Led Indicator
Note:The Battery Output is derived directly from the Load output. Its loading requirements
subtract from the Load current.
1 . The output voltage is only adjustable when the PSU is turned on with no battery connected
to the battery terminals. The adjustable range in the table is the minimum guaranteed range.
Output voltage
Table 1 . Led indicator
Table 2. Output voltage

5
MECHANICAL
Dimensions and Mounting
Mounting Points
The enclosure includes 4 x M3 threaded inserts on the bottom surface to allow the unit do be
screwed to a mounting bracket.
(Centres are located at 1 86.5mm x 63mm spacing)
Feet
The SME240-1 2-20 has 4 x “feet” positioned in the corners of the bottom surface for
bench mounting.

DC Power Output
6
INSTALLATION
Installation should only be conducted and/or closely supervised by appropriately qualified
person.
Mounting Options
The unit is supplied with 4 rubber feet for bench use. owever, a number of mounting options
have been provided to suit various installations. Mounting options have been provided
underneath of unit in the form of M3 x 0.5 mm threads. The unit can be mounted horizontal or
vertical to suit all types of installations.
The maximum thread length for these screws is 4 mm from the outside edge of the power
supply. azardous Voltages exist within the power supply so it is important that the screw
lengths are adhered to.
Connectors
Input Mains: IEC320
Alarm Temperature sensor
1 2 3 4 5 6
Connector Style
6 Way Combicon type with screw terminal plug
eader: Phoenix MC1 ,5/6-G-3,81 (or MCV1 ,5/6-G-3,81 ) or compatible
Plug : Phoenix MC1 ,5/6-ST-3,81 or compatible
34
21
Connector Style
4 Way Combicon type with screw terminal plug
eader: Phoenix PC4/4-G-7.62 or compatible
Plug : Phoenix PCD4/4-ST-7.62 or compatible

7
Excessively long cable connections are not good practice. Try to keep these lines to a minimum to
reduce system voltage drop.
BATTERY (+B) & 0V
These 2 connections are to be connected to the battery.
• Ensure that the battery is connected with the right polarity. Although reverse polarity will
not harm the battery, power supply or the load, no backup of the load will occur during a
power outage.
• Consult battery manufactures data before use with the power supply.
• Excessively long cable connections are not good practice. Try to keep these lines to a
minimum to reduce system voltage drop.
RELAY
The 2 relay connections are the floating alarm relay contacts.
• Connect these pins to any circuit, which is required to be activated by an alarm
condition. The 2 pins become shorted when an alarm condition occurs.
• These pins must not be connected to mains circuits or any other hazardous voltage
circuits.
Cabling
AC Cabling: A cable size of 0.75 mm2 (1 8AWG) is recommended.
DC Cabling: A minimum cable size of 1 .5 mm2 (1 6AWG) is recommended.
Note, maximum size of cable to output connector is 2.5 mm2 or 1 2AWG
DC load cables must be sized to carry the maximum full load current and not exceed the system
volt-drop requirements.
Connection
The requirements for wiring a SME240-1 2-20 into a system are as follows:
LOAD (+L) & 0V
These 2 connections are the DC output of the power supply. These connections are to supply the
load.
• These connections cannot be paralleled with output of duplicate power supply for
increased current output.
• The load connection must not be directly connected to the battery or paralleled with the
battery connection. This will disable the battery low voltage disconnect circuit and defeat
the internal battery fuse.
Voltage Setting
When the PSU is turned on without the battery connected to the battery terminals, the output
voltage may be adjusted within the range specified in table 2.
The output voltage adjustment is achieved in the following way:
• Remove any device from the SMBUS data pins and disconnect any battery.
• To increase the output voltage, short the SMBDATA pin (pin 5) to SMBUS0V (pin 4).
The output voltage will increase by approximately 0.1 V/s
• To decrease the output voltage, short the SMBCLK pin (pin 6) to SMBUS0V (pin 4). The output
voltage will decrease by approximately 0.1 V/s
If a battery is connected, the output voltage will revert to the battery voltage setting.

8
Cooling
The SME240-1 2-20 power supply has inbuilt thermal cooling to maximuse fan life.
Please ensure that there is no restriction to the venting of the unit.
Approval Marking Status
ACMA C-Tick Yes
NSW Fair Trading Approval Number U20348EA Yes
Approvals
SPECIFICATIONS

021 478 DOC BCE282 Series User Manual -B
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