Elgar SmartWave SW1750A, Operation Manual

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Operation SW 5250A•SW 3500A•SW 1750A
3-28 Operation Manual
SELECTION PURPOSE
EXT MOD
(External
Amplitude
Modulation)
Amplitude modulation of an output waveform is possible via an input
signal from the rear panel. Input of 0-5 Vrms corresponds to a modulation
of 0-20%. To allow for the modulation voltage, the maximum prog-
rammed voltage is 130 Vrms in low range, and 260 Vrms in high range.
DIR INPUT
(External
Direct Input)
Input on rear panel allows reference signal to go directly to amplifiers.
A signal of 0–5 Vrms (±7.07 Vpeak) or ±5VDC corresponds to 0 to full
scale programmed voltage output.
CAUTION:
Do not exceed the maximum frequency specification.
EXT GAIN
(External Gain)
Input on rear panel is used to scale output waveform. A 0 to ±7.07 VDC
input signal corresponds to 0 to ±full scale programmed voltage output.
X-LOAD
Reactive Load)
This option can be used to reduce overshoot, undershoot and ringing with
unusual reactive loads. This option should not be used for normal loads.
Do not program frequency >1000 Hz.
LOW FREQ
(Low Frequency)
This option should be used for external AC input signals between DC and
40 Hz (the maximum VA rating must be derated). Also, use for IEC-1000-
3-3 testing, or other conditions requiring fast transient response. The
RMS servo is bypassed. As a result, load regulation drops off, and
current limit (voltage foldback) is disabled.
CLOCK/LOCK
Use this option to configure rear panel clock/lock signal as input or output.
When configured as input, the power outputs will attempt to sync to
clock/lock input frequency. Target output frequency is determined by
frequency value entered in Program Menu FREQ field. Target frequency
should be entered before clock/lock is configured as output. Input
configuration process is as follows:
1. Enter target frequency in Program Menu FREQ field.
2. Go to System External Menu and enable CLOCK/LOCK option by
selecting IN .
3. The unit will now attempt to lock to the input signal; this process can
take up to 5 seconds. Phase lock is indicated on the LCD by the
1
symbol to the right of the OUTPUT [ON/OFF] status. Output relay
will not be allowed to close until phase lock has been established.
4. Close the output relay.
5. Clock/lock input frequency is continually compared to the target
frequency. If input frequency changed more than ±10%, output
relay will open and an error message will be displayed.
When configured as an output, clock/lock signal outputs a square wave
of the same frequency as the power outputs. Select OFF to disable.
OFF will configure clock/lock as an input with the PLL mode disabled.
Table 3–3 System External Menu