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MicroAmps DC (µADC)
Microamps for flame rectifier diode test on a heater control. Connect
leads between flame sensor probe and control module and turn heating
unit on to read µA measurement. When the flame is on, there should be a
measurable µADC signal, typically under 10µADC. Compare measurement
to manufacturer’s specification to determine if replacement is necessary.
Ranges:
1000µA
Resolution:
0.1µA
Accuracy:
±(1.0% + 5)
Volts burden:
5V
Overload Protection:
600VDC or 600VAC rms
Frequency (Hz) Through Leads
Check incoming voltages to ensure they are cycling at 60Hz. For
frequency measurements on VFD equipment, use the amp clamp.
Ranges:
100Hz, 1kHz, 10kHz, 100kHz, 1MHz
Resolution:
0.01Hz
Accuracy:
±(0.1% + 5)
Sensitivity:
10Hz to 1MHz: >3.5Vrms
Minimum PW:
>1µs
Duty Cycle Limits:
>30% and <70%
Duty Cycle (%)
Duty cycle shows the % On Time of a 5V logic signal square wave.
Ranges:
5%-95% (40Hz to 1kHz), 10%-90% (1kHz to 10kHz), 20%-80%
(10kHz to 20kHz)
Accuracy (5V logic):
±(2% + 10)
Resolution:
0.1%
Pulse Width:
>10µs
Overload Protection:
600VDC or 600VAC rms
Capacitance (MFD)
Set to MFD to test motor start and run capacitors. Capacitors are one
of the most failure prone components in a HVACR system. Disconnect
from power and resistors between terminals. Discharge capacitor before
testing. If dIS.C is displayed, the capacitor needs to be fully discharged to
test.
Ranges:
10nF, 100nF, 1000nF, 10µF, 100µF, 1000µF, 10mF
Accuracy:
±(3% + 15) 10nF, ±(3% + 5) 100nF to 1000µF, ±(5% + 5) 10mF
Resolution:
0.01nF
Overload Protection:
600VDC or 600VAC rms
Discharge Cap First!
