Tegam 3550 - Power Switch

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Model 3550 LCR Meter Instruction Manual Operating Instructions
Front Panel Description cont’d:
1 - [POWER] Switch – [POWER]
With the power switch in the down state, power is applied to the 3550 and in the up state power is
off. When the power is turned on, the remaining operational switches will retain the same status
as they had before the power was previously turned off.
If the power is turned on while simultaneously pushing the [MAN/EXT] Key, the machine will
return to its factory default settings.
2 "CIRCUIT MODE" Panel - [AUTO] [SER] [PRL]
This panel contains the keys used for setting the Series or Parallel Equivalent Circuit Mode. When
verifying incoming component values it is usually good practice to consult the manufacturer for the
recommended test mode.
In general, parallel mode is used when the reactance of a device is large. Parallel mode should be
used when a capacitor’s leakage or an inductor’s core losses significantly affects the reading.
Series mode is recommended for small reactance measurements in capacitors and inductors where
series lead resistance must be considered and leakage and core losses become negligible.
x [AUTO] – When this key is illuminated, the instrument is in AUTO equivalent circuit mode.
This means that the 3550 will automatically select either series or parallel equivalent circuit
mode based on the impedance of the DUT. It does not necessarily mean that the correct
equivalent circuit mode will be selected.
x [SER] – Series equivalent circuit mode is typically desirable for low reactance
measurements. This is because Rs or series resistance becomes more significant than
parallel resistance to the measured value.
x [PRL] – Parallel equivalent circuit mode is often more effective for measurement of
impedances with high reactive components. This is because in a capacitor or inductor with
a high reactance, the parallel leakage is more significant to the measured value.
3 "TRIGGER" Panel - [INT] [MAN/EXT]
Select either an internal or external trigger by pressing either the [INT] or [MAN/EXT] key. The
active trigger mode of the 3550 is indicated by an illuminated pushbutton.
x [INT] - When the [INT] key is pressed, the 3550 operates in the continuous trigger mode.
The instrument automatically takes readings at regular intervals.
x [MAN/EXT] – Depressing the [MAN/EXT] key will put the 3550 into manual one-shot trigger
mode, which requires the [MAN/EXT] key to be pressed for each reading.