Spektrum SPM18000 DX18QQ - Manual (Page 17)

17 www.spektrumrc.com EN
Power System Requirements
Inadequate power systems that do not provide the necessary minimum voltage to
the receiver during fl ight are the number one cause of in-fl ight failures. Some of
the power system components that affect the ability to properly deliver adequate
power include:
• Receiver battery pack (number of cells, capacity, cell type, state of charge)
• The ESC’s capability to deliver current to the receiver in electric aircraft
• The switch harness, battery leads, servo leads, regulators, etc.
The X-Plus 8 module has a minimum operational voltage of 3.5 volts; it is highly
recommended that the power system be tested per the guidelines below.
Recommended Power System Test Guidelines
If a questionable power system is being used (e.g., a small or old battery, an ESC
that may not have a BEC that will support high-current draw, etc.), perform the
following test with a voltmeter. The Hangar 9
® Digital Servo & Rx Current Meter
(HAN172) or the Spektrum Flight Log (SPM9540) work well for this test.
Plug the voltmeter into an open channel port in the receiver and, with the system
on, load the control surfaces (apply pressure with your hand) while monitoring the
voltage at the receiver. The voltage should remain above 4.8 volts even when all
servos are heavily loaded.
CAUTION: When charging Ni-MH batteries, make sure the battery fully
charges. Ni-MH batteries charged with peak detection fast chargers have
a tendency to false peak (i.e. not fully charge), which could lead to a crash.
X+6 Servo
To SRXL Port
Auxiliary Battery Pack
(optional)
Jumper
On/Off Switch Harness (optional)
X+5 Servo X+4 Servo X+3 Servo X+2 Servo X+1 Servo
X+8 Servo X+9 Servo