S
srands
Useful reference guide for AMPAGE TESTING of 12 Volt DC.
PICTURE VERSION URL:
https://blufiles.storage.live.com/y...znmbCQXpJVytYH2xzFs/AmpageTesting12VoltDC.jpg
WORD VERSION URL:
https://skydrive.live.com/view.aspx?cid=9EC5688DD90EEC6C&resid=9EC5688DD90EEC6C!581
TOOLS NEEDS:
MULTIMETER, SCREWDRIVERS & BLOCK CONNECTORS
This is quite simple see following pictures (Much easier to do then first impression on reading instructions), the MultiMeter in this instance (DRAWN, POSITIVE TERMINAL) tests the AMPAGE between the POSITIVE SUPPLY (red probe lead) and the POSITIVE LOAD (black probe lead). Hence the NEGATIVE is uninterrupted from SUPPLY to LOAD (In other words, leave it alone). In this instance the positive supply has croc clips, normally I'd use insulated BLOCK CONNECTORS:
PIC1 (multimeter measuring AMPAGE between POSITIVE supply & POSITIVE load)
PIC2 (12V dc Battery Charger powering car cd player, with MultiMeter Testing AMPAGE)
PIC3 (CAR CD PLAYER in house install powered by CAR BATTERY CHARGER 12 V dc 4A)
PRECAUTIONARY NOTEs:
~ Obviously the NEGATIVE and POSITIVE can NOT touch each other (Neither SUPPLY or LOAD)
~ If your MultiMeter has NEGATIVE READING, then means you have your PROBE LEADS the wrong way (Or just ignore the negative symbol, as the AMPAGE figure will be accurate).
~ The 12V dc MOTOR/PART or ALTERNATOR/SOLAR PANEL may CHARGE/DRAW a greater AMPAGE/CURRENT then the capacity of the MULTIMETER & its LEADS (At this point the actual ampage is unknown). For example most car electrical parts are low current (Indicators, elec windows, elec sunroof, heater, etc), with the obvious exception of a car starter motor (Extremely high ampage/current, totally unsuitable for testing with MultiMeter). Hence if the 12V dc part/motor or the charge rate of the power supply is greater then 10A this may melt your MultiMeter probe leads and/or break the MultiMeter (Unless you have a 20A DC MultiMeter! Obviously the ampage max of those is 20A DC).
OTHER NOTES:
~ The AMPAGE reading given by your MULTIMETER, is given by testing 'A' POSITIVE or 'A' NEGATIVE, however the AMPAGE reading is the total AMPAGE drawn/charged, so this figure should NOT be doubled in your calculations.
~ If you're testing direct from a car battery and it's loom, it may have other parts/motors draining ampage, such as indicators/wipers, etc. So turn ON the ignition (WITHOUT STARTING THE CAR, as the ampage drain would be far too great for the MULTIMETER & PROBE LEADS!), then make a note of what the standard ampage drain is approximately (i), then turn on the motor/device/appliance you want to test (ii). Then subtract the standard ampage drain from the new figure with the appliance/device/motor on to EQUAL the difference (iii) i.e. The ampage of the motor/part etc.
FOR EXAMPLE:
i) STANDARD AMPAGE DRAIN = 0.5a (Car alarm or something else)
ii) STANDARD AMPAGE DRAIN & OTHER MOTOR = 1.5a
iii) CALC 1.5a - 0.5a = 1.0a
Alternatively (my preferred practice/method) connect new leads to the battery terminals, so there won't be any other registered ampage drawn from the car battery. So the ampage reading is what it is!
PS. Don't mess about from behind the car fusebox, keep it simple, either direct from car battery and loom OR new power leads from car battery to motor/part/device/appliance your testing with a MULTIMETER.
I made this guide as a quick reference when testing 12 Volt DC circuits with a MultiMeter, EITHER:
~ ampage CHARGE to batteries
OR
~ ampage DRAWN from batteries.The main reason for this guide is that I was not impressed (And continue to be not impressed with the lack of meaningful instructions) with uncomprehensive manuals supplied with most MultiMeters. Seems odd to make a great feature but don't explain in the instructions.
Remember most MultiMeters (£10 Maplin job ok) only test upto 10A 12V DC, more expensive MultiMeters (UNI-T from Maplin £30 why spend any more) test upto 20A 12V DC.
ALTERNATIVELY To test AMPAGE of 240 VOLT APPLIANCES use a plug in ENERGY MONITOR (From Maplin).
This guide I'm sure will be a great help to test 12 Volt DC circuits, however please feel free to add these links below (Website addresses, urls, etc), the numerous number of posts on this subject (That I couldn't find), and web references to wiring regulations, and any other derogatory negative remarks you have as well!
CHEERS, AND BELOW IS A FULL LIST OF MY OTHER USEFUL GUIDES & SPREADSHEETS (Top entries of electrical interest)
STEPHAN RANDS
AMPAGE TESTING (12 Volt DC)
RING AMP AUTOCALC: 1ST TAB
LIGHTING CIRCUITS, RING & RADIAL wiring diagrams
UTILITY ENERGY MEGACALC
MPG
METRIC AUTOCALC
PERCENTAGE CALCULATOR AUTOCALC
EXCEL USEFUL FORMULAS
MTB ROUTES IN/NEAR HULL, HUMBERSIDE
TIER 4+ CATEGORY TYPE
TIER 4+ MONEY TYPE
AUTOCALC WEBSITE
PICTURE VERSION URL:
https://blufiles.storage.live.com/y...znmbCQXpJVytYH2xzFs/AmpageTesting12VoltDC.jpg
WORD VERSION URL:
https://skydrive.live.com/view.aspx?cid=9EC5688DD90EEC6C&resid=9EC5688DD90EEC6C!581
TOOLS NEEDS:
MULTIMETER, SCREWDRIVERS & BLOCK CONNECTORS
This is quite simple see following pictures (Much easier to do then first impression on reading instructions), the MultiMeter in this instance (DRAWN, POSITIVE TERMINAL) tests the AMPAGE between the POSITIVE SUPPLY (red probe lead) and the POSITIVE LOAD (black probe lead). Hence the NEGATIVE is uninterrupted from SUPPLY to LOAD (In other words, leave it alone). In this instance the positive supply has croc clips, normally I'd use insulated BLOCK CONNECTORS:
PIC1 (multimeter measuring AMPAGE between POSITIVE supply & POSITIVE load)
PIC2 (12V dc Battery Charger powering car cd player, with MultiMeter Testing AMPAGE)
PIC3 (CAR CD PLAYER in house install powered by CAR BATTERY CHARGER 12 V dc 4A)
PRECAUTIONARY NOTEs:
~ Obviously the NEGATIVE and POSITIVE can NOT touch each other (Neither SUPPLY or LOAD)
~ If your MultiMeter has NEGATIVE READING, then means you have your PROBE LEADS the wrong way (Or just ignore the negative symbol, as the AMPAGE figure will be accurate).
~ The 12V dc MOTOR/PART or ALTERNATOR/SOLAR PANEL may CHARGE/DRAW a greater AMPAGE/CURRENT then the capacity of the MULTIMETER & its LEADS (At this point the actual ampage is unknown). For example most car electrical parts are low current (Indicators, elec windows, elec sunroof, heater, etc), with the obvious exception of a car starter motor (Extremely high ampage/current, totally unsuitable for testing with MultiMeter). Hence if the 12V dc part/motor or the charge rate of the power supply is greater then 10A this may melt your MultiMeter probe leads and/or break the MultiMeter (Unless you have a 20A DC MultiMeter! Obviously the ampage max of those is 20A DC).
OTHER NOTES:
~ The AMPAGE reading given by your MULTIMETER, is given by testing 'A' POSITIVE or 'A' NEGATIVE, however the AMPAGE reading is the total AMPAGE drawn/charged, so this figure should NOT be doubled in your calculations.
~ If you're testing direct from a car battery and it's loom, it may have other parts/motors draining ampage, such as indicators/wipers, etc. So turn ON the ignition (WITHOUT STARTING THE CAR, as the ampage drain would be far too great for the MULTIMETER & PROBE LEADS!), then make a note of what the standard ampage drain is approximately (i), then turn on the motor/device/appliance you want to test (ii). Then subtract the standard ampage drain from the new figure with the appliance/device/motor on to EQUAL the difference (iii) i.e. The ampage of the motor/part etc.
FOR EXAMPLE:
i) STANDARD AMPAGE DRAIN = 0.5a (Car alarm or something else)
ii) STANDARD AMPAGE DRAIN & OTHER MOTOR = 1.5a
iii) CALC 1.5a - 0.5a = 1.0a
Alternatively (my preferred practice/method) connect new leads to the battery terminals, so there won't be any other registered ampage drawn from the car battery. So the ampage reading is what it is!
PS. Don't mess about from behind the car fusebox, keep it simple, either direct from car battery and loom OR new power leads from car battery to motor/part/device/appliance your testing with a MULTIMETER.
I made this guide as a quick reference when testing 12 Volt DC circuits with a MultiMeter, EITHER:
~ ampage CHARGE to batteries
OR
~ ampage DRAWN from batteries.The main reason for this guide is that I was not impressed (And continue to be not impressed with the lack of meaningful instructions) with uncomprehensive manuals supplied with most MultiMeters. Seems odd to make a great feature but don't explain in the instructions.
Remember most MultiMeters (£10 Maplin job ok) only test upto 10A 12V DC, more expensive MultiMeters (UNI-T from Maplin £30 why spend any more) test upto 20A 12V DC.
ALTERNATIVELY To test AMPAGE of 240 VOLT APPLIANCES use a plug in ENERGY MONITOR (From Maplin).
This guide I'm sure will be a great help to test 12 Volt DC circuits, however please feel free to add these links below (Website addresses, urls, etc), the numerous number of posts on this subject (That I couldn't find), and web references to wiring regulations, and any other derogatory negative remarks you have as well!
CHEERS, AND BELOW IS A FULL LIST OF MY OTHER USEFUL GUIDES & SPREADSHEETS (Top entries of electrical interest)
STEPHAN RANDS
AMPAGE TESTING (12 Volt DC)
RING AMP AUTOCALC: 1ST TAB
LIGHTING CIRCUITS, RING & RADIAL wiring diagrams
UTILITY ENERGY MEGACALC
MPG
METRIC AUTOCALC
PERCENTAGE CALCULATOR AUTOCALC
EXCEL USEFUL FORMULAS
MTB ROUTES IN/NEAR HULL, HUMBERSIDE
TIER 4+ CATEGORY TYPE
TIER 4+ MONEY TYPE
AUTOCALC WEBSITE
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