Beyond INF-B Manual del operador descargar pdf (Pagina 113)

103

External Control Lines

31.12 NONSTANDARD RX (PIN 12) AND NONSTANDARD TX (PIN 13)

These two pins allow digital communications with the meter using 5 V CMOS logic levels and

RS-232 protocols and format. This access is normally reserved for specialized equipment com-

munication in a calibration lab or at the factory.

31.13 NO CONNECTION (PIN 14)

31.14 +V EXT (PIN 15)

This is the pin on which to bring in isolated external 5 to 30 V to power the snubbing diodes of

the four setpoint/alarm open-collector transistors.

31.15 SP1 (PIN 16)

The open-collector of the first setpoint transistor (can carry 150 mA).

31.16 SP2 (PIN 17)

The open-collector of the second setpoint transistor (can carry 150 mA).

31.17 AL1 (PIN 18)

The open-collector of the third setpoint (first alarm) transistor (can carry 150 mA).

31.18 AL2 (PIN 19)

The open-collector of the fourth setpoint (second alarm) transistor (can carry 150 mA).

31.19 RTN EXT (PIN 20)

This is the return to the external ground (P2-20) of the external power for the setpoint transistors

and snubbing diodes brought in on P2-15, 16, 17, 18 and 19. Figure 30-2 shows an example of

a circuit using an external relay with SP1 (Setpoint 1). If a solid state relay is used, delete

connection to Pin 15.

Figure 30-2 For Setpoint Transistors

RELAY

EXTERNAL

DC POWER

16 20

151

1 2 ... 108 109 110 111 112 113 114 115 116 117 118 ... 131 132

Sin comentarios

Beyond INF-B Manual del operador Pagina 113