Mode Control Of The Quad-Mode Dual - Thurlby Thandar Instruments New PL Serie Manual Del Usuario

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 analogue control over the
specified voltage range using the full 300º rotation of the voltage controls.
Because turning V-Span on will always change the output voltage, it can only be enabled or
cancelled with the output off. If attempts are made to enable or cancel V-Span with the output on,
the display will briefly show the message
To set new values for V
The lower voltage limit is defined by using the MAIN and FINE VOLTAGE controls to set exactly
the required value; the V
flashing and the right-hand side (mA) display shows
time by a short press (<1 second) of the V
exactly the same way using the VOLTAGE controls and the V
The limits can be set in any order and to any value within the output range of the instrument but
V-Span can only be turned on with the ENABLE key if V
met, the message
When V-Span is enabled, the range of the MAIN VOLTAGE control is exactly V
the FINE control is set at its mid-point, marked on the panel with a • . The FINE control itself
can be usefully used to give an additional fine adjustment of ±1% (of the voltage span).

Mode Control of the Quad-Mode Dual

However, it is not possible to guarantee that there will never be any unwanted transients as the
mode is switched and the recommendation is therefore that both outputs should always be
switched off before any mode change.
12
is shown briefly in the display and the LOCK indicator is also flashed. If the
or V the V-Span function must be off (cancelled).
min max
key is then held pressed until the left-hand side (V) display stops
min
Set Err is briefly displayed and the V-Span function is not implemented.
The four operating modes of the Quad-Mode Dual are
described below; the mode is changed using the MODE
rotary switch. To prevent unintended voltages being
accidentally applied to the circuits connected to the outputs,
changing modes will always cause both outputs to be
switched off.
V-Span is turned on or off with the ENABLE key. The
ENABLE lamp is lit when V-Span is selected. The
factory default is V
min
turn oFF to prompt the user to turn the output off.
Set . The setting can be VIEWed at any
key. The upper voltage limit is set and VIEWed in
min
max
≥ (V
max
turn oFF is first shown in
= 3V, V = 5V
max
key.
+ 0.1V); if this condition is not
min
to V
min
Unloc
when
max