Hach AF7000 SCM Manual Básico Del Usuario página 12

Fire hazard. Relay loads must be resistive. Always limit current to the relays with an external fuse or
breaker. Obey the relay ratings in the Specifications section.
Refer to the illustrated steps in this section to connect the instrument to external devices or to a
communications network. For connection to the wire terminals, refer to
Option
4–20 mA
Modbus (RS485)
Alarm relays
External PID controller
Digital input
Pin Description
P Phase
N Neutral
E Protective earth ground
1
12 English
W A R N I N G
Table 1 Optional device wiring
Pin name (description)
Sh (shield with ground)
Sh (shield without ground)
NC (normally closed)
Sh (shield)
1 (input 1)
Table 2 Autoflush card wiring
Table 1
Pin name (description)
+ (positive)
Tx (transmit)
Com (common)
+ (positive)
2 (input 2)
Wire color
Black—1
Black—2
Green/yellow
2
and Table 2.
Pin name (description)
– (neutral)
Rx (receive)
NO (normally open)
– (negative)
Com (common)