Technical
Information
Yokogawa Electric Corporation
Sale of the YS80 Series began in January of 1981, with over 1,200,000 units have been shipped since.
Some units have been in operation for a long period of time, and we have been having customers perform re-
placement with the YS80 Style E or YS100 Series for those that have been in use for many years.
Also, sale of the YS100 Series began in January of 1991, so it has been over twelve years since the first items
were shipped, and it is now nearing the time in which preventive maintenance is required.
Various directions can be considered for these instruments that are in operation, according to the situation of
the customer: replacement with the latest version of or successor models, shift to system instrumentation, or
continued use in the current state. But whatever the situation, it is necessary to maintain high reliability while
they are in operation.
Examples of the wear-out failure mode which is known as the bathtub curve include parts with a lifetime, such
as aluminum electrolytic capacitors, as well as parts such as switches with electrical contacts. At the design
stage, the YS Series utilizes parts that have high reliability and a long lifetime, but there are some parts for
which long-term deterioration due to the frequency of use cannot be avoided, as well as parts which deteriorate
due to the operating environment, etc. Leaving such deteriorated parts as they are may lead to serious prob-
lems due to instrument malfunction. Problems believed to be due to the neglect of preventive maintenance also
occur.
In light of such precedents, it is recommended that preventive maintenance required to maintain reliability be
performed at regular intervals for parts which have a lifetime.
Please contact our Service Department regarding preventive maintenance.
Preventive Maintenance for Parts with a Lifetime
It is recommended that the parts given in the following table be replaced at regular intervals.
Item
Major Applicable Models
Recommended
Replacement
Intervals
Notes
Fuse
Aluminum Electrolytic
Capacitor
Backup Capacitor
Fan
Battery
Fluorescent Display Tube
Replay
Fluorescent Tube
Servo Motor
Liquid Crystal Display
∗
: Except YS110
Slide Switch,
Micro Switch
All YS80 models
SDND
All YS100 models(*)
SDND*A
All YS models
SLPC, etc.
1 year, in non-energized state
SLPC, etc.
SKYD, SALD etc.
All YS100 models(*)
SRVD, SRHD
All YS100 models(*)
All YS80 models
(except Style R)
Differs according to the environment and
frequency of use.
3 years
Replece every 8
years without fail.
10 years
3-5 years
5-10 years
5 years in
energized state
3-5 years
600,000
operations
2 years
3-10 years
7 years
Prevents wire breakage caused by element
deterioration.
Vendor-site replacement.
Prevents fluid leaks and capacity drop.
Equivalent to 10 years at a frequency of 1
operation every 10 minutes.
Accoding to the degree of deterioration in
brightness.
According to the degree of deterioration in
brightness.
Accoding to input vibration, etc. (Bearing wear)
Accoding to the degree of contrast decrease.
5-10 years
YS Series
Preventive Maintenance
TI 1B4Y04-01E
TI 1B4Y04-01E
© Copyright June 2004 (YK)
1st Edition June 2004(KP)
