Often times, a voltage and current analysis is
needed to determine the issue. Traditionally, clamp-on
current or Amp probes that read DC voltage have been edgy
and hard to stabilize. The Doughnut Clamp-On Current Probe
is the answer to this problem. There is a huge difference
between AC and DC clamp-on current probes. The AC clamp-on
probes, those you find at Home-Depot or you hardware store,
is a magnetic current probe. It is used by electricians to
troubleshoot home or commercial electrical issues. The AC
current probe has no use in automotive diagnostics. Enter
the DC current probe, which was not even possible a decade
ago. The reason is that DC clamp-on probes utilize special
sensors and circuits to read the passing DC current. Those
developed by Fluke and Tektronix are accurate, but very
expensive and not cost effective for a tech or auto repair
shop.
Why you need the Doughnut Current Probe
That brings us here, to the Automotive Clamp-On Doughnut
Current Probe. The Doughnut is a cost effective, extremely
accurate, rugged, internally supplied circuit and amplified
DC current probe. It can be used with our own Scope-1 or any
other oscilloscope. Why the weird doughnut shape? Simple,
convenience and auto repair applicability. This is not the
only doughnut shape design, but it is the world's first
automotive DC doughnut shape current probe. It is shaped
that way to be able to go deeper into the engine bay wiring
harness. More than anything, it's made that way so that you
are able to uncover a fuel-injector or ignition coil wire
sheathing and connect at least two of these probes. Why at
least two? Simple, you need to compare one injector to
another; and for that you need at least two probes. The idea
is to have a maximum of 8 (8 cylinders) of these doughnut
probes to be able to view a current and voltage signal
waveform at the same time. That's what it's all about,
convenience.
Solution to your problem
So why would you want to be able to view the maximum amount
of cylinders? Why not remove the injector or coil fuse and
tap there? Yes, this is very possible and doable, but not
always. The newer trend is for manufacturers to add more
Oxygen sensors or AFR-Wide-Band sensors. You new see 4
cylinder engines with one O2 sensor for every two cylinders.
Imagine an 8 cylinder engine. In one word, manufacturers
want more control over the air-fuel mixture, down to the
cylinder. That's why this technology was created. That's why
the Doughnut Clamp-On Current Probe was made. You can
certainly get along great with one or better yet two of
these, but the capability and the cost savings is there is
you want to go with a full kit.
The benefits of the
The benefits of the Automotive Doughnut Clamp-On Current
Probe are these: Rugged almost indestructible, has internal
current sensing DC circuitry, the signal is amplified for a
low signal-to-noise ratio, can be used with any oscilloscope
or graphing meter like Fluke, Vantage, Modis, Pico, etc, is
totally integrated with the Scope-1 using the "Signalator"
module, connects to it's own regulated 5 volt very stable
power supply, rock solid signal output worthy of automotive
repair use. The Doughnut current probe comes with all the
needed cables, includes a BNC scope cable-connector, RCA
style 5-volt power cable, signal amplifier conditioner and
filter circuitry and plastic case. The signal amplifier
conditioner and filter protects your oscilloscope. It it
gets zapped by say a spark plug high-voltage, just replace
the included chip and no harm done. We though of everything.
(As a side note, this unit is not meant to test AFR
Oxygen sensors; for which we have another AFR Tester
Unit.)
