Xantrex Technology 18V 10A Benutzerhandbuch

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Operation 
Setting Up the Output 
With the POWER switch on (
l
) and the 
 output off the output voltage and current limit can 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 ON lamp lights; the left-hand meter now shows 
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. 
Protection 
The output has intrinsic short-circuit protection and is protected from reverse voltages by a diode; 
the continuous reverse current must not exceed 3 Amps, although transients can be much higher. 
Connection to the Load 
The load should be connected to the positive (red) and negative (black) OUTPUT terminals. Both 
are fully floating and either can be connected to ground. 
Remote Sensing 
The unit has a very low output impedance, but this is inevitably increased by the resistance of the 
connecting leads. At high currents this can result in significant differences between the indicated 
source voltage and the actual load voltage (two 20m
Ω connecting leads will drop 0.2V at 5 Amps, 
for instance). This problem can be minimised by using short, thick, connecting leads, but where 
necessary it can be completely overcome by using the remote sense facility. 
This requires the sense terminals to be connected to the output at the load instead of at the 
source; insert wires into the spring-loaded SENSE terminals and connect directly to the load.  
Switch the LOCAL/REMOTE switch to REMOTE.  To avoid instability and transient response 
problems, care must be taken to ensure good coupling between each output and sense lead. This 
can be done either by twisting the leads together or by using coaxially screened cable (sense 
through the inner). An electrolytic capacitor directly across the load connection point may also be 
beneficial. 
The voltage drop in each output lead must not exceed 0.5 Volts. 
Switch the LOCAL/REMOTE switch back to LOCAL when remote sensing is not in use.