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All Rights Reserved. Copyright © 1999, Yokogawa M&C Corporation
IM 77J01Q17-01E
8.2
Settings Related to Communication
Function
Set the following parameters when output-2 is specified for com-
munication function. For more information on the communication
function, see the Instruction Manual for VJ Series Communication
Function (IM 77J1J11-01E).
8.2.1
Communication Protocol
Set the communication protocol by selecting from among PC-
LINK, PC-LINK WITH SUM, MODBUS ASCII, MODBUS
RTU, and LADDER in F01: PROTOCOL.
8.2.2
Communication Address
Set the address number of the isolator numerically in a range of 1
to 99 in F02: ADDRESS.
8.2.3
Baud Rate
Set the baud rate by selecting from among 1200, 2400, 4800, and
9600 bps in F03: BAUD RATE.
8.2.4
Parity
Select and set NONE, EVEN, or ODD in F04: PARITY.
8.2.5
Data Length
Select and set 7 bits or 8 bits in F05: DATA LEN.
8.2.6
Stop Bit
Select and set 1 bit or 2 bits in F06: STOP BIT.
8.2.7 Input Decimal Point Position
Namber of digits of decimal places can be set.
Select and set among 0 to 5 digits in F07: INPUT DEC PT.
8.3
Settings Related to Alarm Output
Set the following parameters when output-2 is specified for alarm
output.
8.3.1
Alarm Setpoints
Set the alarm setpoints of alarm-1 and alarm-2 in E03: SET
POINT1 and E04: SET POINT2 numerically.
●
Setting range: A range of 0 to 100% of input range
●
Setting resolution: 0.1%
8.3.2
Direction of Alarm Action
Select the direction of alarm-1 action and that of alarm-2 action from
among HIGH ALM (high-limit alarm) and LOW ALM (low-limit
alarm) and set each in E05: ALM1 ACTION (direction of alarm-1
action) or E06: ALM2 ACTION (direction of alarm-2 action).
●
To activate alarm status when input signal
ⱖ
alarm setpoint,
select HIGH ALM.
●
To activate alarm status when input signal
ⱕ
alarm setpoint,
select LOW ALM.
8.3.3
Hysteresis
Set alarm-1 and alarm-2 hysteresis, in E09: HYSTERESIS1 and
E10: HYSTERESIS2. Hysteresis is a value added to the alarm
setpoint in order for an alarm status to be released (to normal) after
the alarm status has been activated. The alarm status will be re-
leased in the following conditions, depending on the direction of
alarm action.
*
When HIGH ALM (high-limit alarm) is set: Alarm is released
when input signal < (alarm setpoint - hysteresis).
*
When LOW ALM (low-limit alarm) is set: Alarm is released
when input signal > (alarm se hysteresis).
●
Setting range: A range of 0 to 100% of input range
●
Setting resolution: 0.1%
8.3.4
Alarm ON Delay and Alarm OFF Delay
Set alarm-1 and alarm-2 ON delays in E11: ON DELAY1 and
E12: ON DELAY2 and then alarm-1 and alarm-2 OFF delays in
E13: OFF DELAY1 and E14: OFF DELAY2.
An alarm ON delay is a delay time from the establishment of alarm
condition to alarm output; an alarm OFF delay is a delay time from
the establishment of return-to-normal condition to output.
●
Setting range: 0 to 999 seconds
●
Setting resolution: 1 second (Note that about 0.2 second will
be added to set time to prevent erroneous operation.)
For example, when an alarm ON delay is set to 1 second, alarm
output is generated if alarm status continues for more than 1 sec-
ond after the input value exceeds the alarm setpoint. Further, when
an alarm OFF delay is set to 2 seconds, alarm output is released if
normal condition continues for more than 2 seconds after the input
value has returned to normal from the alarm status.
8.3.5
Direction of Relay Action
Set the direction of relay energizing in alarm-1 normal condition
and alarm-2 normal condition by selecting from among NRM DE-
ENERGIZED (de-energized under normal condition) and NRM
ENERGIZED (energized under normal condition) in E15: RL1
ACTION and E16: RL2 ACTION and set them.