Newport LDC-3706 Series, Руководство пользователя

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December 2019 93 LDC-3706 Series Laser Controller
LASER CONTROLLER
Power on, but no current output Check the interlock pins on the LASER input connector on
the instrument rear panel. These pins must be shorted either
directly or through a switch.
If an “Open Circuit Error” is shown on the display, check the
load connections and then try again.
Check the OUTPUT ON switch, the corresponding LED
should be lit.
Output current at limit, cannot be
lowered If POWER mode is used, check the monitor diode
(feedback) connections. Try reversing the polarity of the
monitor photodiode. Check the photodiode bias adjustment
in the LASER (PARAMETER) menu.
If in constant current mode, check the current set point and
current limit setting. Setting the output below the limit may
require several turns of the adjust knob if the set point is
much greater than the desired limit setting.
Output goes off intermittently Check the interlock circuit. An intermittent interlock will turn
the output off.
Check that the AC power cord connection is secure. Power-
line drop-outs may reset the unit and when power is
restored, the output will be off.
Unable to adjust output Check the LASER (ADJUST) indicator, the indicator must be
lit for any LASER adjustments to be made.
Check the I LIMIT parameter for the output range in use and
that it is set above 0 mA.
Power Mode operation has high output
current, but little or no power is
measured Check the PD BIAS setting. If it is set too low, the power
control mode may act as an open feedback loop. If in doubt,
set the PD BIAS to mid-range (2.5 V).
Ensure that the current limit is set correctly according to
laser manufacturer’s datasheet.
Output exceeds Power Limit The "Power Limit" is not a hardware limit. It only serves as a
warning that the power measurement has exceeded the limit
set point.
Ensure that the current limit is set correctly according to
laser manufacturer’s datasheet.
Open Circuit Error occurs during
calibration Check load connections. Check that measuring meter does
not auto-range (use non-auto-ranging modes).
Calibration is aborted unintentionally Calibration modes will be aborted if an error is detected.
VOLTAGE LIMIT indicator blinks This indicates a voltage limit error. Check laser connections.
A high impedance may cause this condition.
Open circuit error E503 or Voltage Limit
error E505 prevents output from
reaching desired value. The LDC-3706 has an adjustable laser compliance voltage.
Check to see if the LASER voltage limit setting is too low
(see Chapter 2). Check laser connections.