Operation Manual

GMC-I Messtechnik GmbH 21
Measurement Types
You can choose one of two different types of measurement:
• Measuring sequence with automatic polarity reversal (reversal
of current flow direction)
• Manual measurement with specified current flow direction
8.1 Measurement with Automatic Polarity Reversal – AUTO Function
Automatic polarity reversal is selected as a default value. MAN
does not appear at the display.
Ð Start measurement in both current flow directions by briefly
pressing the START key for one-time polarity reversal or start
continuous measurement for permanent polarity reversal by
briefly pressing the CONTIN. key.
After the measuring sequence has been started, the instrument performs
measurement with automatic polarity reversal, first with current flow in
one direction (
Ω→ ), and then in the other ( ←Ω ). DATA blinks at the display
until the measured value has settled in. The larger (worst) measured value
is displayed. ←Ω→ appears at the display.
Difference > 10%
If, during measurement with automatic polarity reversal, the difference
between
Ω→ and ←Ω is greater than 10%, the resistance values for
both polarities (current flow directions) are displayed separately (sepa-
rated by an underscore). Δ Rlo>10% appears at the display.
Limit Value Indication
If the measured value is less than or equal to 2 Ω, the Limit LED
lights up green. If the measured value is greater than 2 Ω, the LED
lights up red. As a prerequisite, the LiLED parameter must be set
to “on” (see page 13).
Resistances which do not demonstrate a stable value until after a
“settling in period” should not be measured with automatic polar-
ity reversal. Measurement with automatic polarity reversal may
lead to varying and/or inflated measurement values, and thus to
an ambiguous reading.
Ω→
←Ω
ΔRlo>10%:
←Ω & Ω
→
AUTO: Ω→
DATA
00.1
DATA
00.7
Rlo
07._0.1
Δ Rlo>10%
Ω→
Rlo ←Ω
DATA
Limit
< Limit R
LO
= OK 3
←Ω
ΔRlo ≤ 10% ? ←Ω→
ΔRlo > 10% ? ←Ω & Ω→