RS-232 Troubleshooting: 
If there is RS-232 connection problem, check the following: 
1.  Computer  and  power  supply  must  configure  the  same  baud  rate, 
parity,  data  bits  and  flow  control  options.  Note  that  the  power 
configuration as a start bit and a stop bit (these values are fixed). 
2.  As described before in RS-232 connector, you must use the correct 
interface cable or adapter. Note that even if the cable has the right 
plug, the internal wiring may be wrong. 
3.  Interface cable must be connected to the correct serial port on the 
computer (COM1, COM2, etc.). 
Communication Settings 
Before communication, you should first make the following parameters 
on the power supply and PC matches. 
Baud  Rate:  9600  (4800,9600,19200,38400,57600,115200).  You  can 
enter the system menu from the front panel, and then set the baud rate. 
  Data bits: 8 
  Stop Bits: 1 
  calibration (none, even, odd) 
  EVEN          8 data bits, have even parity   
  ODD            8 data bits have odd parity 
  NONE          8 data bits, no parity   
  MODE: (SIG,MUX) 
  SIG    a single instrument is connected to the communication   
  MUX    multiple sets of instrument communication with PC at the same time, 
in this situation, instrument address must be set to distinguish among all 
the units(address    0  ~30, default set is 0) 
Local Address: (0 ~ 30, the factory default setting is 0) 
 
4.2 USB interface   
Use a Cable with two USB port to connect the power and the computer. 
All power functions can be programmed via USB. 
The USB488 interface functions of the power supply described as below: 
  interface is 488.2 USB488 interface. 
  Interface  Receive  REN_CONTROL,  GO_TO_LOCAL,  and