TOA Electronics FPS1000-12, FPS-S1U Internal temperature measurement, Typical application diagram

7.5.3 Internal temperature measurement

The internal ambient temperature is measured to provide information of the safe operation of the power supply. The internal ambient temperature is usually higher than the power supply air intake temperature due to internal power dissipation. As the power dissipation varies with the load, the internal ambient temperature increases with the load. Refer to Fig 7-2 for typical internal temperature rise above the air intake temperature versus the load.

Internal temp. rise (°C)

15

10

5

0

25 50 75 100 % of rated load

Fig 7-2: Internal temperature rise vs. load

Internal temperature calculation example:

1.Hex readback: 68 (0110 1000).

2.Convert hex readback to decimal: 104

3.Calculate the measured temperature:

Temp=104*0.391=40.664oC

7.6 Typical application diagram

A typical application is described in Fig 7-3.

PC

RS232

RS232

CABLE

RS232 TO

I2C

CONVERTOR

			ON/OFF
			CONTROL
CLOCK	SIGNAL	ON/OFF		+S
	RETURN			+V
SCL
DATA	FPS1000
SDA
				-V
GND	A0	A1	A2	-S
				ADDRESS
				SETTING

+

LOAD

-

Fig 7-3: Typical application of I2C interface

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