Uses:

• Car battery current is measured with the cable connected normally. Parasitic drain, charging and cranking current are shown without the need to disconnect a cable.
• Power plant battery float charge and load current are measured with the battery on line and connected.
• Control 4 to 20 mA loop current is measured with the control on line, without the hazard of breaking a loop while a power or chemical plant is running.
• Sacrificial or impressed anode current is measured by cliping around the cable. There is no need to open the cable or add shunts which increase resistance, and may blow with lightning. Likewise with bonds.
• Interference current in a large gas pipe, steel reinforced concrete column, or telephone cable is measured with the line in service.
• Flange leakage current is measured in an operating gas, oil or water pipe.
• Foreign contact or ground faults are located when other devices fail.
• Offshore platform aluminum anode current is measured at a depth of hundreds of feet. This shows that electrical contact is good, and implies how long the anode will last.
• Current in a propeller or pump shaft is measured while the shaft is rotating.
• Guy wire or anchor rod current drain to ground is measured when only a short section is handy.
• Electrolytic current flowing in brine in a pipe, or in salt water, is measured like any other current.
• The algebraic sum of current in a steel conduit plus the current in conductors inside the conduit are measured by clipping over the outside of the conduit.
• Differential control line leak to ground is measured and the fault located with the line operating.
• URD bare outer conductor resistance is measured to find local corrosion, with the cable live and in service.

Advantages of DC Amp Clips:

• They work in high noise environments of power plants.
• Currents in URD concentric neutral, pump shafts, and transmission pipe can be measured while in service.
• Differential leakage current -- even current flowing inside steel conduit -- may be measured.
• Interference current can be recorded using a recorder jack which multiplies the unattended meter span by up to 5 times.
• If two or more conductors are in the aperture of a sensor, the reading is the algebraic sum of all currents.
• The indicator shows the average magnitude of current whether it is DC, pulsating, AC, or a combination.
• Alternating current is rejected so that 10 amp. AC interference will change a measurement less than 5 mA.
• A brief 200 amp. overload on any range will not alter the zero or damage the meter.
• Accuracy is good even if a conductor is not centered in the aperture of the sensor.
• Current flowing outside the sensor is rejected.

   

Recorder:

• On any range a recorder jack (rcdr) has ± 2.0 volt output whenever the digital meter reads full scale.
• 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 permits the user to do the work of two men. It is also a backup in case the LCD meter is damaged.

Accuracy:

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 to 2/3 the He rating if the full Floating Zero procedure is followed with experience and skill.

Our optional 70 mA Tester may be used to verify the accuracy of direct current Swain Meters.

Model Code:

100-LCD-200-MER-¾" MER Sea Clip (13" MER™Sea Clamp) (Box)

is a DC Amp Clip which has:

• 3½-digit LCD meter with polarity and ½" high numerals
• 200 amp. maximum current reading
• ¾" aperture clip primary sensor with direct calibration
• 13" clamp secondary sensor with its calibration chart
• wooden carrying and storage case for everything