Ac Measurement; Indicator Lights; Auto-Off - AEMC MR521 User Manual

AC Measurement

 Select the appropriate AC mV or V range on the DMM or measuring
instrument.
 The DC zero adjustment is not required when measuring AC current
with a voltmeter that is AC coupled. The DC zero adjustment is
required if you are using a voltmeter that is DC coupled.
 Select the appropriate mV AC or V AC range on the DMM or
measuring instrument.
 Clamp the probe around the conductor (1) to be tested. The display
device should now display the measured conductor current. Apply the
conversion ratio (1mV/A or 10mV/A) to get the value of the current.
Indicator Lights: Green LED and Red LED
 The green LED indicates that the probe is on and that the battery is
good. The green LED will not light under low battery conditions.
Replace the 9V battery if the green LED is not lit.
 The red LED indicates a momentary or continuous overload of the
instrument. Readings taken while the red LED is on or flashing should
be considered inaccurate. Momentary or continuous currents
exceeding 60A peak on the 60A range or 600A peak on the 600A
range for the Model MR411, and 150A peak on the 150A range or
1500A on the 1500A range for the Model MR521 will trigger the red
LED.

Auto-Off

 The Models MR411 and MR521 have an Auto-Off feature which turns
off the instrument after 10 minutes if no control has been used.
 When the probe is switched off by this automatic function, the switch
must first be set to the off position before the probe may be powered
up again.
 Auto-off may be disabled at power-up by the user. Simply press the
auto zero button at the same time as moving the switch from the OFF
position to one of the ranges. The green LED blinks three times to
indicate that the auto-off is disabled.
AC/DC Current Probe Models MR411 & MR521
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