is one of the ESR meters from EVB
in sunny Portugal (CRed
version). They're the same basic design as the Anatek Blue meter,
and there are various versions to suit individual needs.
The black (SBX CX) version has heavy duty protection diodes in parallel with the test leads while the white (SWX) version is designed to be able to test batteries, so it doesn't have those diodes. It still has reasonable protection against charged capacitors. This new "CX" version is powered by 6x AA cells and is housed in a stronger ABS case. Unlike the Anatek meter, it has an easy to understand chart of typical capacitor ESR figures on the front. ;-)
These meters are available fully-built from EVB in Portugal (click here) so check them out.
Brief Specifications...Measurement range: 0.01 to 99 ohms, auto-ranging
Peak voltage across capacitor under test @ full scale: 50mV
Update speed: 4 readings/second
Power supply: 6x AA cells or 9V battery (depending on model)
Controls: Single push button for power on/off and zero
Dimensions: EVB: 65mm x 131mm x 30mm.
Microcontroller: ZiLOG Z86E0412PSC 1866
* Test lead resistance compensation.
* Automatic power off when reading is unchanged for 3 minutes.
* Low battery voltage warning ('b' flashes on right-hand digit).
* Big, easy to read 0.5 inch (13mm) LED displays.
* Table of typical good capacitor ESRs on the front panel.
* Kits contain all hardware and components, except batteries (prohibited in postal system).
Note: A variable DC power supply is needed to calibrate the kit meters. Click here for a little circuit you can make if you don't have one.
Overload ToleranceThese ESR meters can generally handle being connected to capacitors charged to about 50V without damage, but like most other ESR meters they will be seriously damaged by being connected to such things as the main filter capacitor charged to 300V or more, of a 240V-powered switching power supply. Some versions of the EVB meter have extra protection as noted above.