Tri-M Systems HE104 - Manual (Page 9)

23 June 2005
HE104MAN-V8 Manual
Tri-M Engineering Tel: 800.665.5600, 604.945.9565
1407 Kebet Way, Unit 100 Fax: 604.945.9566
Port Coquitlam, BC V3C 6L3 E-mail: [email protected]
Canada Web site: www.tri-m.com
8
2.2 Power Considerations
Usable +5V output =10A – (I [-5] + I [-12]
•
2.4 + I [12]
•
2.4)
0.8
The +5V switching regulator is rated at 10A maximum output however, the +5V output, supplies
power to the +12VDC, -5VDC and –12VDC regulators. To obtain the usable range of +5V output,
“derate” according to the use of +12VDC, -5VDC and –12VDC. Use the following formulae to
calculate the maximum usuable output.
Where: I[-5] = -5VDC current load
I[-12] = -12VDC current load
I[12] = 12VDC current load
Assuming 90 percent convertor efficiency (actual efficiency may vary).
2.3 HE104 Connectors
2.3.1 Main Input Power Connector
Input power is connected to the “pluggable” block, CN1, which is removable from the socket
connector on the circuit board. The power supply accepts DC input voltages in the range of
6VDC to 40VDC.
Unregulated vehicle power is connected as follows:
-Terminal 1: “hot” polarity
-Terminal 2: Common (0VDC)
!! CAUTION !!
To allow operation at the lowest possible input voltages (6VDC) and for the best efficiency, there is
no input Reverse Polarity Diode (RPD) provided on the HE104 without a battery charger option. If
input RPD is required, add RPD to the HE104 part number:
- Example HE 104-512-16-RPD
Note: Adding the RPD results in an increased power loss. For heat dissipation estimation please
refer to section 2.11.