Model Boat Mayhem
Technical, Techniques, Hints, and Tips => The "Black Arts!" ( Electrics & Electronics ) => Topic started by: Nordsee on July 10, 2011, 05:24:54 pm
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I have just bought one of these instruments, and although I have read the very sketchy instructions, can find no mention of if I can use it as an Ampmeter, and if yes, how!! Can any of you bright guys put me out of my misery!!??
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A photograph of the front panel would be an asset here, methinks :-))
Ken
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I am assuming you have a large dial on the front of your merer, with various segments marked about its circumference. Look for a segment marked 'A' or amps, this will be subdivided into various ranges ie. 20 micro amps, 2000 micro amps 50 Milli amps 5 amps etc. allways select the highest range and work down, so you don't inadvertently damage the instrument. Ammeters are allways connected in series, voltmeters in parallell.
Hope this helps,
Nick
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Here is a photo. I have switched it on, hence the illuminated display. The Instructions are more concerned with disposing of the old battery, maybe they assume only people that know what they are about will buy one...
(http://s2.postimage.org/31yphaup0/P7110004.jpg) (http://postimage.org/image/31yphaup0/)
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Hi Nordsee,
To measure DC current up 10Amps, you must change the red lead to the connection next to the 10A DC position, then set the range selector switch to this position.
The meter must then be be connected in series with the motor or the circuit being checked.
The most convenient way, normally, is to remove one battery lead, and connect this to one lead of the instrument, then connect the other instrument lead to the battery terminal.
When the circuit is then switched on, the current will be displayed on the meter.
As it is a digtal instrument, the polariy of the connection is not critical, it will simply indicate a -ve figure if connected in 'reverse'.
I hope this helps.
If you have any questions, feel free to pm me.
Peter
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Hi Nordsee,
To measure DC current up 10Amps, you must change the red lead to the connection next to the 10A DC position, then set the range selector switch to this position.
The meter must then be be connected in series with the motor or the circuit being checked.
The most convenient way, normally, is to remove one battery lead, and connect this to one lead of the instrument, then connect the other instrument lead to the battery terminal.
When the circuit is then switched on, the current will be displayed on the meter.
As it is a digtal instrument, the polariy of the connection is not critical, it will simply indicate a -ve figure if connected in 'reverse'.
I hope this helps.
If you have any questions, feel free to pm me.
Peter
Thank you :-)) :-))
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make sure its in series ..you'll blow the fuse on the meter..
and ..if theres more than 10amp current the same well happen if connected correctly.
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In the picture of the meter, the 10A connection is actually marked as "UNFUSED".
Now that could lead to a few very interesting happenings. :o
Regards
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Hi, Nordsee
Here is a photo. I have switched it on, hence the illuminated display. The Instructions are more concerned with disposing of the old battery, maybe they assume only people that know what they are about will buy one...
(http://s2.postimage.org/31yphaup0/P7110004.jpg) (http://postimage.org/image/31yphaup0/)
I found this
http://www.doctronics.co.uk/meter.htm
which seems to be a very similar or identical instrument
It only measures current (amps) DC and if you look at the Right hand side of the dial there is a sector labelled DCA (DC Amps) with 4 different selections which go from micro amps to milliamps - it will read to an amp or two on the 200m scale
below this there is the 10A scale whicch seems to be the one you wish to use - the other guys have been helpful with this
(If you want to know WHY you plug the lead into tthe different socket - it has a loop of copper fencewire (the shunt) which carries the (up to 10A) current and then actually works out the current which is flowing by looking at the voltage drop over the fencewire
SO - do not worry too much about blowing a fuse - there are only milliamps flowing in the actual meter whatever the current in the shunt
ask us 'owt
andrew
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SO - do not worry too much about blowing a fuse - there are only milliamps flowing in the actual meter whatever the current in the shunt
However, all of the current will be flowing in the wires, which might or might not be capable of surviving it. As a good mate once said, having observed the effects of forgetting what the meter was set for, "Welding rods are cheaper".
Many meters with a 4 digit readout have the leftmost digit as a blank or one, thus giving a reading up to 19.99 A. A bit of crossed fingers involved, and a high reading through those thin test leads might not be the entire truth, and certainly not for more than a very few seconds, since the leads become the fuse.
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I have read all the replies, thanks very much for your good advice. It seems it is a bit of a Minefield useing one of these if you are at all doubtful, so I will just confine my usage to reading voltages! It is an instrument that was sold by LIDL, so maybe you have had them in UK? Also Lidl stuff is usually quite good. Thanks again.
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You have yourself a good general purpose meter that most certainly has it place on any work bench :-))
If measuring DC amps is of importance to you, Its not that hard to build up a test station. Im gathering bit's to build my own volt/ammeter station with internal power supply.
I'll post some pics when I finally get all the bits together if you wish.
It consist of an old 12amp car 12v battery charger,an analog volt meter,analog Ammeter. It will max out at 20 amp's
these meters are cheap.
http://cgi.ebay.ca/DC-85C1-15V-Analog-Volt-Voltage-Panel-Meter-Voltmeter-/390313615945?pt=AU_B_I_Electrical_Test_Equipment&hash=item5ae0812249
http://cgi.ebay.ca/85C1-Analog-Current-Panel-Meter-DC-20A-20-AMP-Ammeter-L-/120686639187?pt=LH_DefaultDomain_0&hash=item1c197bf853
At some point, I may try to get the voltage variable...
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Hi Nordsee.I've got an instrument identical to yours!
Great little device. Cheap and cheery, but invaluable to have when setting up your boat.(or anything!)
I made 2 heavier duty leads with clips on the ends,
Mick
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You have yourself a good general purpose meter that most certainly has it place on any work bench :-))
If measuring DC amps is of importance to you, Its not that hard to build up a test station. Im gathering bit's to build my own volt/ammeter station with internal power supply.
I'll post some pics when I finally get all the bits together if you wish.
Yes, Please. :-)) :-))