Sagetech XPC-TR User Manual - page 9
9
XP Transponders User Guide Rev 1.3
Zener diodes are used on the DC Power pins to protect the transponder against overvoltage and reverse
polarity.
Electrical connections to the transponder, including DC power, are defined in detail in Appendix C of this
document.
Sagetech recommends use of an appropriate amperage inline fuse for the supplied current.
Table 2
– Maximum Current Consumption
Variant
Supply Voltage
Max Average
Current
Note
XPC-TR Mode C Transponder
10 V
1.1 A
Measured
32 V
0.4 A
Measured
XPS-TR Mode S Transponder with ADS-B Out
10 V
1.2 A
Measured
32 V
0.4 A
Measured
XPS-TRB Mode S Transponder with ADS-B In/ Out
10 V
1.4 A
Estimated
32 V
0.5 A
Estimated
Important:
Transponder inrush current when the transponder is switched from OFF/STBY to
ALT/ON is as follows (all variants): 6A at 32v and 4A at 10v. Contact Sagetech if you
need actual graphical data depicting inrush current for your particular application.
Thermal Management
The XP transponder is designed so its case conducts thermal load to the aircraft frame. The transponder
can be firmly mounted directly to the aircraft, or to other components within the aircraft.
The transponder should be mounted away from sources of excess heat to better guarantee an operating
environment within its designed temperature range.
Control Interface
Sagetech XP transponders are controlled with a straightforward communication system via a serial
interface (RS-232 port).
Sagetech provides a Transponder Interface Cable (part number XP-CBL-001) which includes a
transponder-side connector and is un-terminated at the flight control side. Electrical connections to the
transponder, including serial interfaces, are defined in detail in Appendix C of this document.