SAFETY INSTRUCTIONS Precautions when working with batteries. - Batteries contain very corrosive diluted sulphuric acid as electrolyte. Precautions should be taken to prevent contact with skin, eyes or clothing - Batteries generate hydrogen and oxygen during charging resulting in evolution of explosive gas mixture.
PRINCIPLE OF OPERATION * NOTE: Depending upon the version of the unit, Schottky Diode D1 & D2 may be any of the following alternatives: • 175BGQ030, or • 182NQ030, or • 3 pcs of 72CPQ030 in parallel Please refer to the schematic diagram at Fig. 1 The power supply is connected to the positive and negative input terminals.
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In a battery backup application, the battery will normally remain in a fully charged, standby condition most of the time. It will discharge to the load only when the power supply fails. Under this standby application, the battery should be charged at the recommended float voltage. Assuming the standby float charging voltages of 12 V / 24 V sealed lead acid (SLA) batteries to be 13.5 V to 13.8 V and 27 V to 27.6 V ( at 60ºF to 77ºF) respectively, the output voltage of the power supply should be adjusted as follows:...
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If the power supply fails, the load will be supplied by the battery through the Schottky diode D2. As in the case of diode D1, there will be a forward voltage drop of 0.2 to 0.4 V across D2. Thus, when the battery is supplying the load, the voltage seen by the load will be 0.2 to 0.4 V less than the battery voltage.
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Calculating maximum battery charging current Max. charging current Ib = {(Vp – Vd) – Vb} divided by Rs ……. Equation 1 where, Vp = The output voltage of the power supply Vd = Forward voltage drop across D1 (0.2 V for < 1 A and 0.4 V > 10 A) Vb = Battery voltage at fully discharged condition (Normally 11.4 V for 12 V and 22.8 V for 24 V) Rs = Equivalent series resistance (In this case, two 1 Ohm in parallel = 0.5 Ohm)
INSTALLATION CABLE SIZING, TERMINATION AND FUSING The size of the cables used to connect the power supply, the battery and the load to this unit will depend upon the maximum value of the current flow and the length of the cable run. Current flowing through a cable will produce an undesir- able voltage drop along the length of the cable.
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CONNECTIONS Before the power supply is connected to this unit, it is to be ensured that the output voltage of the power supply is adjusted to the required voltage as ex- plained under “Principle of Operation” on page 3. Switch off the power supply. Connect the positive and negative output of the power supply to the input terminals of the unit marked “INPUT POSITIVE”...
SPECIFICATIONS Input voltage 14 VDC for 12 V battery 27.6 VDC for 24 V battery Input current Up to 100 A Output Voltage 0.4 V less than the input voltage (At 10 A) i.e. • 13.6 VDC for input voltage of 14 VDC for 12 V battery •...
2 YEAR Limited Warranty The BBM-12100 manufactured by Samlex America, Inc. ( the “ Warrantor “ ) is warranted to be free from defects in workmanship and materials under normal use and service. This warranty is in effect for 2 years from the date of purchase by the user ( the “ Purchaser “) For a warranty claim, the Purchaser should contact the place of purchase to obtain a Return Authoriza- tion Number.
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