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MER Meter with 2" MER Sea Clip
The MER (Magnetic Error Reduction)
model Swain Meter is a 1% clamp-on DC ammeter for measuring line
current and direction of flow.
Ideal for measurements near static
magnetic fields
With Magnetic Error Correction, MER
Meters are faster and simpler to use when measuring direct current on
steel pipe, near rebar, or a battery cable on a vehicle. Accuracy is
better when measuring small currents because the zero offset error due
to local magnets is reduced. Generally, a short two-step floating zero
correction suffices.
Ideal for undersea or underground
measurements
Offshore platform anode currents or
transmission line currents can be measured at 700 ft. depth or more. MER
Clips (to 6" dia.) and Clamps (to 60" dia.) work undersea for a long
time when waterproof connectors are provided. Hommema, a Swain Meter
customer, has permanently installed Sea Clamps six feet below ground to
measure interference current flowing in a gas pipeline.
Upgrade to automatic operation
The newer Swain Meter
AutoMER Model combines Magnetic Error Reduction with automatic
control, where range and zero are set automatically.
Meter Description
- User friendly 3½ digit LCD meter
with polarity & 0.5" high numerals.
- Calibrated with 3/4" to 6"diameter
current clips or 6" to 60"+ diameter current clamp, as ordered.
- 3 full-scale ranges: 2A, 20A, 200A.
- 1 mA resolution on 2A range.
- Typical meter accuracy is ± 1% reading, ±
2 digits, ± He.
(He
is zero offset sensitivity of the sensor to the Earth's magnetic
field. The Earth field is uniform unless steel is close and distorts
it. A strong magnet nearby can also cause zero offset.)
- When the current is flowing in or
near a magnetic material such as steel, and it is small and cannot
be interrupted, the zero offset due to the sensor may be many times
the He
rating. This error can likely be reduced if the full Floating Zero procedure is followed with
experience and skill.
- AC input current is rejected to less
than 5 mA change with 10A rms, 60 Hz input.
- Recorder connector with ±2 V full
scale output, plus overrange.
- Portable, with auto off, or full on
for recorder.
- 50-hour alkaline internal battery.
- Optional external battery operation.
- Protected from 300 A overload.
- Optional 70
mA Meter Tester and 700 mA Meter Tester to verify
meter accuracy.
Meter Recorder Jack
- A recorder jack (rcdr) provides an
analog voltage output proportional to the reading. On any range, the
full-scale output is ± 2.0V.
- DC Amp Clips will record for two
days on their internal battery, or for over a week with an external
battery (EB) connector.
- When used with a timed data logger,
the recorder jack allows the user to do the work of two men. It is
also a backup in case the LCD meter is damaged.
Meter Model Number
with Current Clip
The model number of a specific Swain
Meter is an abbreviated specification. For example:
100-LCD-200-MER-3/4" MER Sea Clip (13" MER Sea Clamp) (Box).
This is a is a DC Amp Clip which has:
3½-digit LCD meter with polarity
and 0.5" high numerals
200A maximum current reading
3/4" aperture clip primary sensor with direct calibration
13" clamp secondary sensor with its calibration chart
Wooden carrying and storage case for everything
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