AND AD-4530 Instruction Manual page 15

Control input
(6) COM Input COMMON terminal.
(7) LATCH Inputs the latching signal for the function settings and outputs.
(8) HOLD Inputs the hold signal.
(9) ZERO Inputs the zero correction signal.
5.1.3 Relay output connector (Option)
(1) COM Relay output COMMON terminal
(2) LO Relay LO output terminal
Outputs LO when the measured value is less than the lower limit.
(3) OK Relay OK output terminal
Outputs OK when the measured value is equal to or greater than the
lower limit and equal to or less than the upper limit.
(4) HI Relay HI output terminal
Outputs HI when the measured value is greater than the upper limit.
Comparator output
To prevent damage, do not exceed the rated capacities of the output relays.
To protect the output relays, use a varistor, CR circuits or diodes.
5.1.4 Serial communication connector (Option)
In the case of RS-232C:
(1) IC Connected internally (Do not use)
(2) IC Connected internally (Do not use)
(3) SG Signal ground terminal
(4) TxD Sending terminal
(5) RxD Receiving terminal
In the case of RS-485 (Two wire connection):
(1) B B terminal
(2) A A terminal
(3) SG Signal ground terminal
(4) B B terminal
(5) A A terminal
* Each of the A and B connections has two terminals.
These terminals are connected internally and can be used for a terminating resistor
or multi-drop connection.
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