Aim TTi EL-R Serie Manuel D'instructions page 7

All connections are made from the front panel.
The load should be connected to the positive (red) and negative (black) terminals marked
OUTPUT. Both are fully floating and either can be connected to ground.
Remote sense connections to the load, if required, are made from the positive (+) and
negative (−) SENSE terminals. Switch the LOCAL/REMOTE switch to REMOTE when remote
sensing is required. Switch back to LOCAL when remote sensing is not in use.
The terminal marked
Switching On
The POWER switch is located at the bottom left of the front panel. When the POWER switch is
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turned on ( ) the right hand meter briefly indicates the firmware revision before the display
shows Volts and Amps.
Setting Up the Output
With the POWER switch on (
be accurately preset using the VOLTAGE and CURRENT controls; the left-hand meter shows the
set voltage and the right-hand meter shows the set maximum current.
When the output switch is switched ON, the
actual voltage and the right-hand meter the actual load current.
Constant Voltage
The output voltage is adjusted using the coarse and fine VOLTAGE controls; the CURRENT
control sets the maximum current that can be supplied.
Constant Current
If the load resistance is low enough such that, at the output voltage set, a current greater than
the current limit setting would flow, the power supply will automatically move into constant current
operation.
The current output is adjusted by the CURRENT control and the VOLTAGE controls set the
maximum voltage that can be generated.
The CC lamp lights to show constant current mode.
Instantaneous Current Output
The current limit control can be set to limit the continuous output current to levels down to 10mA.
However, in common with all precision bench power supplies, a capacitor is connected across
the output to maintain stability and good transient response. This capacitor charges to the output
voltage and short-circuiting of the output will produce a current pulse as the capacitor discharges
which is independent of the current limit setting.
Efficiency
To improve efficiency at low output levels the overhead voltage to the output regulators is
automatically switched by a relay to a lower voltage; hysteresis at the threshold point prevents
unnecessary switching when the output voltage is set at about that level. Apart from an audible
'click' the user will be unaware that the relay has switched; there will be no disturbance on the
output. The higher power 15V/5A and 30V/3A models use electronic pre-regulation, instead of
relay control, to maintain a low overhead voltage.
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is connected to the chassis and safety earth ground.
Operation - Main Outputs
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) and the output OFF the output voltage and current limit can
Connections
lamp lights; the left-hand meter now shows the