Programming instructions

Indicators
Multisim Component Reference Guide 11-2 ni.com
11.2 Ammeter
The ammeter offers advantages over the multimeter for measuring current in a circuit. You
can use an unlimited number of ammeters in a circuit and rotate their terminals to suit your
layout.
Resistance (1.0 pΩ - 999.99 W)
The ammeter’s resistance is preset to 1 mΩ, which presents little resistance to a circuit. If you
are testing a circuit that has low resistance, you can lower the ammeter’s resistance even
further to get a more precise measurement. (However, using an ammeter with very low
resistance in a high-resistance circuit may result in a mathematical round-off error.)
Mode (DC or AC)
The ammeter is preset to DC mode, which measures only the DC component of a signal. If
you want to measure the current from an AC source, change the mode to AC. When set to AC,
the ammeter displays the root-mean-square (RMS) value of the alternating signal.
Connecting an Ammeter
Like a real ammeter, the simulated ammeter must be connected in series at nodes you want to
measure. The negative terminal is on the side with the heavy border. If an ammeter is moved
after the circuit has been simulated, activate the circuit again to get a reading.
11.3 Digital Probe
The probe indicates high (on) or low (off) levels at any point in a digital circuit. It lights up or
turns off as the circuit is running, and is available in a number of colors.
Placed Probe
Probe in “On” state
during simulation
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