Xantrex Technology XDL 35-5TP Manuale Utente

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Range Selection 
The instrument has three ranges: 35V/3A, 15V/5A and 35V/500mA.  The selected range is shown 
by an illuminated indicator below the appropriate legend at the top right-hand side of the 
instrument; when the 35V/500mA range is selected the indicator legend is mA to emphasise that 
the current meter now shows milliamps not amps. 
To change range press SHIFT followed by RANGE or RANGE; each press of RANGE 
selects the next range to the left; each press of  RANGE selects the next range to the right; 
there is no 'wrap-round'.  When the range is changed the indicator that represents the new range 
and the OK key both flash; pressing OK sets the new range.  To exit without changing range 
press ESCAPE.  Pressing any other key whilst in range change mode causes the warning buzzer 
to beep twice; no other action is taken.  If OK is not pressed within 10 seconds of the last range 
change key press the range selection remains unchanged. 
The range can only be changed when the output is off.  Pressing the  RANGE or RANGE  
keys with the output on will cause the output ON/OFF key (as well as the OK key) to flash.  The 
output may be turned off with the ON/OFF key and the range then changed by pressing OK, or 
OK may be pressed directly in which case the output is automatically turned off and the range 
then changed.  
If a range change causes a voltage or current limit setting to exceed the corresponding maximum 
of the new range the range change is accepted but the setting is made equal to the maximum of 
the new range. 
Note that the OVP setting is not changed when the range is changed (e.g. an OVP setting of 38V 
remains valid on the 15V range); it is left to the user to independently change the OVP setting if 
required.   
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 instrument 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 
capability.  
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 REMOTE SENSE terminals and connect directly to the 
load. 
Select remote sense by pressing SHIFT, SENSE; the OK key flashes and the lamp above the 
remote sense terminals lights to show that remote sense will be selected when OK is pressed.  
Press OK to confirm; press ESCAPE to exit without changing state.  Remote sense is turned off 
by pressing SHIFT, SENSE again; the OK key flashes and the remote sense lamp goes off to 
indicate that local sense will be restored when OK is pressed.  Press OK to confirm; press 
ESCAPE to exit without changing state. 
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. 
The XDL 35-5TP has rear panel output and sense terminals, appropriate for when the instrument 
is used in a rack.  The rear panel sense terminals should always be used with the rear panel 
output connections. 
  
 
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