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BATTERY

MONITOR BM-1

Compact

NASA

BM-1

Compact

V&A

TIME

%

100%

h

80

60

40

TIME TO DISCHARGE, hours

DESIGNED AND

MANUFACTURED

IN ENGLAND

RoHS

2002/95/EC

Summary of Contents for BM-1 Compact

Page 1: ...BATTERY MONITOR BM 1 Compact NASA BM 1 Compact V A TIME 100 h 80 60 40 TIME TO DISCHARGE hours DESIGNED AND MANUFACTURED IN ENGLAND RoHS 2002 95 EC ...

Page 2: ...T INSTALLATION OF THE DISPLAY UNIT NORMAL OPERATION SWITCHING THE BACKLIGHT SHOWING THE TIME TO GO SHOWING THE VOLTAGE AND CURRENT SETTING UP SETTING THE BATTERY CAPACITY SETTING THE ZERO CURRENT BATTERY MANAGEMENT BASICS QUESTIONS AND ANSWERS 2 2 2 2 2 5 6 6 7 7 8 8 9 11 1 ...

Page 3: ... to full discharge during discharging A visual indication of the state of the battery charge is always available and an alarm is used as an alert when the battery voltage falls to a preset level INSTALLING THE DISPLAY Safety notes IMPORTANT Lead acid batteries can emit hydrogen when in operation Hydrogen and air forms a potentially explosive mixture Accordingly ensure that the area around the batt...

Page 4: ...inst the panel face Screw the unit to the panel and connect the wires to the terminal block provided Connect the shunt cable to the display unit as shown on Figure 1 above using the terminal block supplied Be careful to connect the wires exactly as shown noting that the black and white wires are joined at the shunt connection and are connected separately at the instrument end of the cable It is go...

Page 5: ...ACK WHITE WHITE Cables supplied Original cables WHITE YELLOW YELLOW YELLOW BATTERY SHUNT FUSE Black White MUS T NO T be joine d a t thi s end C a b l e S u p p l i e d BM 1 Compact V A TIME Figure 1 Wiring Installation 5 4 TO LOADS AND CHARGERS ...

Page 6: ...ete the electrical installation The BM 1 Compact will now begin assessing the battery state using its factory default values The default values must be set to the values appropriate to the new installation as discussed in SETTING UP below Do NOT put the battery on charge immediately Apply a load to the battery by switching on lights or instruments and wait for a few minutes for the BM 1 Compact to...

Page 7: ...age Time to Go Figure 2 shows the display when the TIME key is pressed The remaining battery capacity in digits as a percentage and analogue thermometer displays and the up to date estimate of how long it will take to charge or discharge the battery fully are shown If the current changes the estimate of the time updates continuously reflecting the best estimate of time to be fully charged or fully...

Page 8: ...e estimate of capacity may become unreliable It is important to switch some load onto the battery for a few minutes so a reliable estimate can be calculated and its value settles before starting charging SETTING UP Setting up can be done after applying power to the unit while one of the keys is pressed This procedure prevents inadvertent changes being made by an unfamiliar user Applying power is u...

Page 9: ...ENT If no current is flowing into or out of the battery and yet a small residual current is shown on the display the reading can be adjusted to zero Ensure that no current is flowing into or out of the battery Turn off the unit With the TIME key pressed re apply the power Release the key SET A is briefly displayed to show that the zero current is to be changed The TIME key increases the setting an...

Page 10: ... battery is 5 Amps because 100 20 5 Likewise a 40 Ah battery would have a 20 hour rate of 2 Amps because 40 20 2 If higher currents than the 20 hour rate are drawn from the battery the available capacity is reduced For example if it is steadily discharged at 10 times the 20 hour rate 50 Amps from a 100Ah battery the available capacity falls to about half of the stated capacity The battery will be ...

Page 11: ... The BM 1 Compact has an alarm which flashes the bell symbol when the voltage falls below 10 7 Volts If the alarm is triggered it is important to reduce the current being drawn immediately and if possible place the battery on charge to avoid permanent damage to the cells If the alarm is ignored the total number of charge discharge cycles which the battery will survive before it loses a substantial...

Page 12: ...hrough the shunt Can the BM 1 Compact monitor my engine starting battery as well as my service battery No it cannot The service battery is in continuous use and so needs continuous monitoring The starter battery however is subject only to periodic heavy loads followed by float charging and so does not need to be monitored I have another voltmeter on my vehicle which shows a different value to the ...

Page 13: ...city it may need replacement or you may feel that changing the nominal capacity from the Engineering mode will suffice to let you know well enough the percentage charge remaining When on heavy load the time to run is lower than I expect Is this correct YES When heavily loaded a lead acid battery delivers less energy than expected owing to electrolyte exhaustion and stagnation When the battery is d...

Page 14: ... prudently and check its operation from time to time against other data Inspect the installation from time to time and seek advice if any part thereof is not fully seaworthy Nasa Marine Ltd warrants this instrument to be substantially free of defects in both materials and workmanship for a period of one year from the date of purchase Nasa Marine Ltd will at its discretion repair or replace any com...

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