YOKOGAWA YS1700 User Manual

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IM 01B08B02-01EN
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Troubleshooting
How to Take Actions if the ALM Lamp or FAIL Lamp Lights up
In detecting an abnormality, YS1000 lights up the lamps (FAIL, ALM) at the upper part of the instrument’s front panel.
• FAIL lamp (red): Lights up if a major failure occurs in which the controller cannot operate.
• ALM lamp (yellow): Lights up if a minor abnormality occurs in which the controller can still continue to operate.
Actions to be Taken if the ALM Lamp Lights Up
• If the ALM lamp lights up, the alarm item can be checked on the ALARM Display.
• Alarm types include STC alarms, process alarms, and system alarms.
• An STC alarm or process alarm that has occurred prior to a power failure will be stored in the memory and will be re-displayed
upon a HOT start. (Even if the power supply is turned off while in the condition that an alarm occurred in and the instrument is
reused without a control module function, the ALM lamp lights up again at HOT start. In this case, set the instrument once to
COLD start and turn ON the power supply. This will clear the alarm indication.)
Table 10.1 List of Causes of Alarm Occurrence
Type
Alarm
Display
Description Cause of Alarm Occurrence and Diagnosis Actions and Others
System
alarm
X1,X2,X3,
X4,X5,X6,
X7,X8
Input overrange
Inputvalueislessthan−6.3%orgreaterthan
+106.3%.
The operation mode (C, A, M) does
not change in the event of alarm
occurrence.
Check wiring and instruments
connected.
Y1,Y3
Current output wire open
or output read-back error*.
Output 1 (Y1) or output 3 (Y3) output wire is
open or output read-back value error*.
Check wiring and instruments connected
or Remove the noise of wiring.
CALC
Computation
overflow
The results become infinite or non-numerical
in the midst of the execution of computation by
user programs in the YS1700 programmable
mode.
Computation based on a limit value
(positive or negative maximum value)
Correct user programs and then
perform download again.
OVER
Exceeding of control
period
Control computation by user programs
exceeds the control period in the YS1700
programmable mode.
During normal run: Computation stops
at 2nd exceeding of the control period.
During test run: Computation stops.
Correct user programs and then re-
download them.
PROG User program error
No END instruction
Out of a device number range
RTN instruction error
User programs are suspended.
Correct user programs and then re-
download them.
DATA
Writing from
YSS1000 incomplete
Data write from YSS1000 has not been
completed.
Re-download data from YSS1000.
COMM
RS-485
communication error
Framing parity error
Buffer overflow
Character-to-character timeout
Error detection (checksum, CRC, LRC)
Check communication connection
(wiring and communication
conditions).
DCS-LCS
communication error
Framing parity error
Buffer overflow
Header receiving data error
Framing parity error
Error detection (BCC)
Communication undetected
Communication time exceeded
Communication status error
Check communication connection
(wiring and communication
conditions).
Check connection destination.
Peer-to-peer
communication error
Framing parity error
Buffer overflow
Receiving data error
Error detection (checksum)
Check communication connection.
ETHER
Ethernet
communication error
No response from Ethernet communication
device
Press the [ALM CLR] software key
to confirm the ETHER alarm. If the
above operation is repeated many
times, it is judged as a failure.
PTOP
Peer-to-peer
communication error
Peer-to-peer communication registers used by
the user programs have not been updated.
Check communication connection.
Check connection destination.
CALR Adjustment inspection error
Contact YOKOGAWA’s sales office
or sales representative.
* An output read-back error is when SCOCD is set to ALARM (1). (Please see P.62)

YOKOGAWA YS1700 Specifications

General

Brand	YOKOGAWA
Model	YS1700
Category	Controller
Language	English