Performance Tests
HP E-Series Power Sensor Interface Test
2-14 HP EPM-441A/442A Service Guide
HP E-Series Power Sensor Interface Test
The HP E-series power sensors have their sensor calibration tables stored 
in EEPROM which enables the frequency and calibration factor data to be 
downloaded automatically by the power meter. The frequency and 
calibration factor data have checksums which are compared with the data 
downloaded by the power meter. For the HP EPM-442A dual channel 
power meter, this test should be performed on both channels.
Procedure
1. When there is no power sensor connected to the Channel A input 
the message “No Sensor” (“No Sensor ChA” on the 
HP EPM-442A) appears on the measurement window. 
2. Connect the HP E-series power sensor to the power meter’s 
Channel A input. The message “Reading Sensor ChA” appears. 
When all the data is downloaded this message disappears and a 
reading is displayed on the measurement window. If the download 
fails, a warning message and error flag are displayed on the front 
panel. Also, SCPI error message “-310, System Error” is 
generated.
3. For the HP EPM-442A repeat these steps for Channel B.
4402serv.book  Page 14  Monday, March 11, 2002  11:34 AM