Dmm Probe
Help building a high voltage probe?
When experimenting with high voltage from flyback transformers etc (don’t worry I know what I’m doing), it would be nice to know exactly how much voltage I’m using without exploding my multimeter.
According to these two links I found it seems fairly simple to make one, but I have some questions.
Here are the links:
http://www.kronjaeger.com/hv/hv/msr/elc/
http://www.geocities.com/CapeCanaveral/lab/5322/hvprobe.htm
1) The 2nd link says use a 1kohm resistor with a DMM so why doesn’t the first link mention this? Left it out by mistake?
2) On which side of the 1kohm resistor should I put each lead from my multimeter?
3) What does the 2nd link mean by a ’50uA panel meter’? A basic panel voltmeter?
I know I’m only really supposed to ask one question at a time here but any help you can give is appreciated 
The DVM has an internal resistance of about 10 megohms. The first link is using this along with the external 1 Gohm resistor to give a ratio of 100:1, so 50 kv will read 500 volts on the DVM. In the second link, a resistor is put in parallel with the meter so that there is a known resistance, and the ratio will become 1000000:1, and a voltage of 50 kv will read as 50 mv. The important thing is that the resistance of the meter is known, so that the ratio is accurate. Some DVM’s have different amounts of resistance on different scales. If you use a higher value of resistance across the meter, like 1 Mohm to give a ratio of 1000:1, remember that your resistor is in parallel with the meter. So if the meter resistance is 10 Mohm, you need about 1.11 Mohm in parallel. By the way, the 2nd link says to put the 10 Mohm resistors in parallel — they should be in series.
A 50 uA panel meter is an analog meter which is used in a lot of the old VOM’s. It is sensitive to current, not voltage, so you don’t need a parallel resistor. The 1Gohm resistor will give you a full-scale reading of 50 kv.
Fluke Multimeter probe repair
|
|
Tektronix THS730A Handheld Multimeter Oscilloscope/DMM, 200MHz w/ 2 P6117 Probes $1,350.00 |
|
|
HP 3478A Digital Multimeter 5 1/2 Digit, No Probes $219.99 |
|
|
UNI-T UT81B SCOPEMETER MULTIMETER OSCILLOSCOPE DMM DVM SCOPE PROBE UTC01 HOOKS $216.99 |
|
|
New High Voltage low noise probe for scope + DMM 15KV 1000:1 Tektronix OEM made $215.62 |
|
|
UNI-T UT81B SCOPEMETER MULTIMETER OSCILLOSCOPE DMM DVM SCOPE PROBE UTC01 HOOKS $214.99 |
|
|
New High Voltage low noise probe for scope + DMM 15KV 1000:1 Tektronix OEM made $211.65 |
|
|
UNI-T UT81B SCOPEMETER MULTIMETER OSCILLOSCOPE DMM DVM SCOPE PROBE USB INTERFACE $208.99 |
|
|
FLUKE 80T-IR Non-Contact Infrared Temperature Probe DMM $199.99 |
|
|
ATD 5597 Digital High Current Probe/DMM NEW IN BOX!!!!! $199.99 |
|
|
Automotive Logic Probe with DMM and Oscilloscope $197.50 |
|
|
ATD 5597 Digital High Current Probe/DMM $195.69 |
|
|
Electronic Specialties ESI655 1000 Amp Probe Digital Multimeter $187.71 |
|
|
ATD-5597 Digital High Current Probe/DMM $187.21 |
|
|
Fluke 27 Digital Multimeter w/manuals and carrying case w/ 80K-6 and 85RF probes $167.00 |
|
|
ATD 5597 DIGITAL HIGH CURRENT PROBE/DMM *NEW* $175.00 |
|
|
Low Current Probe/Digital Multimeter ESI687 $171.08 |
|
|
1000 Amp Probe Digital Multimeter ESI655 BRAND NEW! $168.56 |
|
|
Electronic Specialties 687 Low Current Probe/digital Multimeter $163.89 |
|
|
Electronic Specialties 655 1000 Amp Probe Digital Multimeter $161.93 |
|
|
HIGH-VOLTAGE PROBE FOR DMM DC 0-30KV AC 0-20KV 1000Mohm $149.00 |
|
|
655 1000 Amp Probe Digital Multimeter $155.94 |
|
|
Electronic Specialties 655 1000 AMP CURRENT PROBE/DMM $150.95 |
|
|
PDI Model 920 Automotive DMM DIGITAL MULTIMETER w/ PROBE LEADS $150.00 |
|
|
Fluke 27/FM Digital Multimeter, 80K-6 High Voltage Probe,and Hard Case $135.00 |
|
|
HIGH-VOLTAGE PROBE FOR DMM DC 0-20KV AC 0-14KV 1000Mohm $139.00 |
|
|
ESI 655 1000 AMP CURRENT PROBE/DMM $147.85 |
|
|
Low Current Probe for Graphing Meters, Scopes and DMM’s ESI695 BRAND NEW! $142.98 |
|
|
Low Current Probe for Graphing Meters, Scopes and DMM’s $130.61 |
|
|
FLUKE 27 DIGITAL MULTIMETER With High voltage Probe $139.99 |
|
|
Electronic Specialities 687 Low Current Probe Digital Multimeter $138.62 |
|
|
Electronic Specialties 687 Low Current Probe/DMM Tester $129.95 |
|
|
Elec. Specialties 655 High Current Probe/DMM Tester $126.95 |
|
|
ESI Low Current AC/DC Probe Graphing Meters,Scopes,Dmm $129.99 |
|
|
FLUKE Digital Multimeter DMM 85 RF High Frequency Probe $129.99 |
|
|
Low Current Probe for Graphing Meters, Scopes and DMM’s $129.99 |
|
|
Electronic Specialties 1000AMP Probe Digital Multimeter $118.99 |
|
|
ES 687 LOW CURRENT PROBE / DMM Automotive, HVAC & More $117.99 |
|
|
FLUKE 87 True RMS Digital Multimeter w/ 80TK Thermocouple Module & 80i-400 Probe $101.99 |
|
|
Tektronix DM501A DM 501A OPT 002 Digital Multimeter Plug In Probe $90.00 |
|
|
Fluke 27 Digital Multimeter with Two Fluke 1500V Probes, Slightly Waterproof $119.99 |
|
|
Fluke 8050A Digital Multimeter w/ Probes & Hard Case & EXTRAS $100.00 |
|
|
FLUKE 189 DIGITAL MULTIMETER TRUE RMS i410 AC/DC CURRENT CLAMP PROBE/CLAMP KIT $99.00 |
|
|
Equus Innova 3347 Digital Multimeter AMP Probe $101.96 |
|
|
Equus Innova Digital Multimeter Inductive AMP Probe $88.99 |
|
|
Products EPI3347 Digital Multimeter AMP Probe $97.29 |
|
|
Equus Products 3347 Digital Multimeter AMP Probe $95.91 |
|
|
Digital Multimeter Inductive AMP Probe EQS3347 BRAND NEW! $92.83 |
|
|
Digital Multimeter AMP Probe EPI3347 $90.17 |
|
|
Digital Multimeter AMP Probe EPI3347 $88.99 |
|
|
Fluke 8050A Digital Multimeter w/ Probes $74.95 |
|
|
SIMPSON MODEL 461 DIGITAL MULTIMETER METER & PROBES/POWER SUPPLY IN GOOD CONDITI $74.95 |
|
|
Fluke 8050A Digital Multimeter w/o Probes $72.95 |
|
|
BK PRECISION 2802A DIGITAL MULTIMETER w/PROBE & CARRYING CASE $85.00 |
|
|
10 Multimeter Meter DMM TL36 Test Lead Probe 1KV 1000V $79.99 |
|
|
10 Multimeter Meter DMM TL36 Test Lead Probe 1KV 1000V $79.99 |
|
|
10 Multimeter Meter DMM TL36 Test Lead Probe 1KV 1000V $79.99 |
|
|
PHILIPS PM9246 30K 30000 DMM Meter Voltage High Voltage HV Banana Plug Probe $79.99 |
|
|
UEI DM600 ‘The Pistol’ Digital Multimeter High Quality Unit incl. probes & clips $69.99 |
|
|
Fluke 8010M Digital Multimeter $49.00 |
|
|
Simpson 467 digital Multimeter w Case and Probes $62.99 |
|
|
Extech EX450 True RMS Autoranging Multimeter with Infrared Thermometer $119.99 Compact and powerful, the Extech EX450 Eight-Function True RMS Professional MultiMeter provides the versatility of multiple meters in one convenient device. The EX450 measures AC/DC voltage and current, resistance, diode, and temperature. It also includes a built-in, non-contact infrared thermometer that allows you to detect invisible hot spots, as well as a True RMS function for correcting any di… |
|
|
Fluke 80T-150UA Universal Temperature Probe $206.95 Fluke 80T-150UA Universal Temperature Probe… |
|
|
Digital Multi-Meter w Temperature Probe One of the must-have tools for electric RC pilots and drivers, this digital multimeter provides versatility at an affordable price. It’s extremely easy to use but still has all the features advanced modelers will need. It has an adjustable stand, back light, a tough, removable outer case, and a 9V battery as its power source. — Specificatons: Measures AC/DC voltage, DC Current, continuity, resist… |
|
|
Equus 3320 Auto-Ranging Digital Multimeter $18.99 Eliminate the need to dial in the correct range Has a 10 MegOhm input Large digital display Protective rubber corner guards for drop protection Includes attachable test leads, holders and standAuto-Ranging™ scales eliminate the need to dial in the correct range when making electronic measurements. Has a 10 MegOhm input impedance for safe automotive and household uses (i.e., household ou… |
|
|
Equus 3340 Automotive Digital Multimeter $69.95 Pro quality features help pinpoint engine problems Auto-Ranging, auto shut-off, over-load protection with a 10 MegOhm impedance prevents damage to ECU Tests alternator diodes, duty cycle, solenoids, breaker points, wiring, switches, and more Automatic zero adjustment, reverse polarity protection Monitors vehicle RPM (including Coil On Plug vehicles) Tests alternator diodes, duty cycle, soleno… |
|
|
Fluke 88VA Series V Deluxe Automotive Multimeter Kit $408.99 Series V Deluxe Automotive Multimeter KitA complete automotive diagnostic package. Improved measurement functions, trouble-shooting features and accuracy to solve more problems on conventional and hybrid vehicles. Built-in thermometer lets you carry one less tool (temperature probe included). Resistance, continuity and diode test. RPM measurements with inductive pickup (included). Millisecond puls… |
|
|
SE Clip Test Lead Set (10 Piece) $3.00 10 Pc Set, Color Coded vinyl covered alligator clips. Each clip is crimped to ensure a good conduction. Good quality clips that close well and a strong spring to keep it closed. 10 piece set contains two of each: Black, red, white, green, and yellow. 22 gauge heavy insulation copper wire, 12 in. length…. |
|
|
Extech TL809 Electronic Test Lead Kit $15.99 Parts come in a 3 compartment Velcro® sealable nylon pouch that organizes and protects your test leads — INCLUDES: * (2) PVC Lead Extensions * (1) Heavy Duty Test Probe handles with banana plug tip * (2) Plunger mini-hooks * (2) Alligator Clips with removable insulators * (1) Nylon Pouch… |