Over-temperature Protection
An internal sensor will detect over-temperature due to blocked airflow, fan failure or other circuit
fault. Over-temperature will turn the output off, the OUTPUT indicator will flash, and the display
will show the message
removed, and the instrument has cooled down, the output indicator will go off but the message
OtP triP
continues to show. Pressing the OUTPUT key once will change the display to show
the preset voltage and current (the SETTINGS indicator will be lit) but the output will remain off;
pressing it a second time will turn the output on normally.
If the OUTPUT key is pressed while the instrument is still over-temperature (OUTPUT indicator is
flashing), the message
SETTINGS indicator will be lit) but the output will remain off; each subsequent press of the
OUTPUT key causes the
off until the over-temperature condition ends.
View Settings
Lock Settings
Pressing the LOCK key digitally locks the set voltage and current limit. The settings are stored
with a precision of better than 1 digit. Subsequent adjustments of the VOLTAGE and CURRENT
controls will have no effect.
Because canceling LOCK will cause the output settings to change if the VOLTAGE and
CURRENT control positions have been moved, warning reminders are given before LOCK is
cancelled. Press and hold the key to cancel LOCK.
If the OUTPUT is off (the safe condition) the display will flash the 'unlocked' settings twice before
the change is implemented; the LOCK lamp goes off.
Releasing the LOCK key at any time while the display is flashing will abort the LOCK cancellation.
Attempting to change the current limit range (see Setting up the Output section) or the voltage
span limits (see Voltage Span section) with LOCK enabled is not allowed; if attempted, the
message
Unloc
output is also on when these actions are attempted the message
the display (accompanied by the output indicator flashing) followed by the message
(with the LOCK indicator flashing).
Using Voltage Span
The VOLTAGE SPAN (V-Span) capability allows the end-stop values of the VOLTAGE controls to
be redefined by the user such that the controls operate within a specific, narrower, voltage range.
This not only has the advantage of protecting against the accidental application to the load of
voltages outside of the range, but also provides high-resolution analog control over the specified
voltage range using the full 300º rotation of the voltage controls.
16
OtP triP
. When the cause of the over-temperature has been
OtP triP
is replaced by the preset voltage and current (the
OtP triP
message to be displayed briefly but the output will remain
The set voltage and current limit are always shown when
the output is off but can also be viewed when the output is
on by pressing the VIEW key; the SETTINGS indicator is lit
whilst the VIEW key is pressed.
If the output is still on,
display, followed by flashing of the new 'unlocked' settings for 2-3
seconds (slowly at first, then faster) before the change is finally
implemented; the LOCK lamp goes off when the change is made.
is shown briefly in the display and the LOCK indicator is also flashed. If the
OP on
(output on) will flash twice in the
turn oFF
is first shown in
Unloc