Hitachi Weather Radio EH-150 Benutzerhandbuch

                                                                             3.Specification

3-1

Table 3.1 shows the specifications of EH-PT4.

Type

EH-PT4

Resistance temperature detective

Platinum resistance temperature detective Pt100

                                           (IEC 751)

Platinum resistance temperature detective Pt1000

Temperature conversion data

Signed 15 bits  (In normal state the lowest bit is always “0”.)

Accuracy -20 to + 40 

°

C (Pt100)

±

 0.5 

°

C

(Note 1)

-50 to + 400 

°

C (Pt100)

±

 3 

°

C

-50 to + 400 

°

C (Pt1000)

±

 6 

°

C

Temperature measurement range

-20 to +40 

°

C / -50 to +400 

°

C

(2mA constant current method)

Number of channels

4 channels

Conversion time

About 1s / 4 channels

Insulation  Between channel and PC

Photocoupler insulation

 Between channels

Non-insulation

External power supply

24V DC 

±

10% 100mA max.

Internal current consumption
(5 V DC)

200mA max.

External wiring resistance

400 ohm max. / channel

External wiring

Shielded wire

Additional function

Linearization

Error detection
     -20 to +40 

°

C  (Pt100)

     -50 to +400 

°

C (Pt100/ Pt1000)

H7FFF is outputted at –25 

°

C or less, or at +45 

°

C or higher

H7FFF is outputted at –60 

°

C or less, or at +410 

°

C or higher

Processing for disconnection (Note 2)

H7FFF is outputted to channel.

Note 1: The accuracy is the value when 10 minutes pass after the start of power feeding. Just after

power is fed, the value may increase slightly. Because a resistance temperature detective
has an error, confirm it beforehand.

Note 2: This is the case when the current terminal wiring is broken. In case the voltage terminal

wiring is broken, the data becomes unspecified. (“H” of “H7FFF” means the following data is

hexadecimal.)