XT00-SM00004 EN
1/2
Instruction Manual
Load Sensor
Series:
XT477
Model:
XT477-3
The intended use of this product is to covert a load to output pressure. It is
possible to construct an all air balance circuit by combining it with an air
cylinder and an air operated type precision regulator, etc.
Validated according to ISO13849.
Refer to the Specifications section for details.
1 Safety Instructions
These safety instructions are intended to prevent hazardous situations
and/or equipment damage. These instructions indicate the level of potential
hazard with the labels of “Caution,” “Warning” or “Danger.”
They are all important notes for safety and must be followed in addition to
International Standards (ISO/IEC)
*1)
, and other safety regulations.
*1)
ISO 4414: Pneumatic fluid power - - General rules relating to systems.
ISO 4413: Hydraulic fluid power - - General rules relating to systems.
IEC 60204-1: Safety of machinery - -Electrical equipment of machines.
(Part 1: General requirements)
ISO 10218-1: Manipulating industrial robots -Safety.etc.
This manual contains essential information for the protection of users and
others from possible injury and/or equipment damage.
•
Read this manual before using the product, to ensure correct handling,
and read the manuals of related apparatus before use.
•
Keep this manual in a safe place for future reference.
•
To ensure safety of personnel and equipment the safety instructions in
this manual must be observed, along with other relevant safety
practices.
Warning
•
The compatibility of the product is the responsibility of the person
who designs the equipment or decides its specifications.
•
Since the product specified here is used under various operating
conditions, its compatibility with specific equipment must be decided by
the person who designs the equipment or decides its specifications
based on necessary analysis and test results. The expected
performance and safety assurance of the equipment will be the
responsibility of the person who has determined its compatibility with the
product. This person should also continuously review all specifications of
the product referring to its latest catalogue information, with a view to
giving due consideration to any possibility of equipment failure when
configuring the equipment.
•
Only personnel with appropriate training should operate machinery
and equipment.
The product specified here may become unsafe if handled incorrectly.
1 Safety Instructions - continued
The assembly, operation and maintenance of machines or equipment
including our products must be performed by an operator who is
appropriately trained and experienced.
•
Do
not
service
or
attempt
to
remove
product
and
machinery/equipment until safety is confirmed.
1) The inspection and maintenance of machinery/equipment should only
be performed after measures to prevent falling or runaway of the driven
objects have been confirmed.
2) When the product is to be removed, confirm that the safety measures
as mentioned above are implemented and the power from any
appropriate source is cut, and read and understand the specific product
precautions of all relevant products carefully.
3) Before machinery/equipment is restarted, take measures to prevent
unexpected operation and malfunction.
•
Contact SMC beforehand and take special consideration of safety
measures if the product is to be used in any of the following
conditions.
1) Conditions and environments outside of the given specifications, or
use outdoors or in a place exposed to direct sunlight.
2) Installation on equipment in conjunction with atomic energy, railways,
air navigation, space, shipping, vehicles, military, medical treatment,
combustions and recreation, or equipment in contact with food and
beverages, emergency stop circuits, clutch and brake circuits in press
applications, safety equipment or other applications unsuitable for the
standard specification described in the product catalogue.
3) An application which could have negative effects on people, property,
or animals requiring special safety analysis outside the scope of
ISO13849 stated in this document
4) Use in an interlock circuit, which requires the provision of double
interlock for possible failure by using a mechanical protective function,
and periodical checks to confirm proper operation.
•
Always ensure compliance with relevant safety laws and standards.
All electrical work must be carried out in a safe manner by a qualified
person in compliance with applicable national regulations.
Caution
•
The product is provided for use in manufacturing industries.
The product herein described is basically provided for peaceful use in
manufacturing industries.
If considering using the product in other industries, consult SMC
beforehand and exchange specifications or a contract if necessary.
If anything is unclear, contact your nearest sales branch.
2 Specifications
2.1 Specifications
Table 1
Model
XT477-3
Max. operating pressure
0.8MPa
Output pressure
0.05 to 0.5MPa
Input/output characteristics
Refer to input/output characteristics.
Linearity
±5%F.S or less
Applicable cylinder bore
50mm
Recommended load weight
40kg or less
(Note
１
)
Ambient and fluid temperature
-5 to 60
℃
（
no freezing
）
Operating fluid
Air
Filtration
5
µ
m
Lubrication
Not required
Port size
Rc1/4
Construction
Relief type
Standard
Conforms to basic & well-tried safety
principles of ISO13849
B
10
800,000 cycles
(Note2)
B
10
ｄ
1.6 million cycles
(Note2)
Weight
Approx. 2kg
Note 1) This value takes inertia into consideration. Please avoid eccentric
load as much as possible.
2 Specifications - continued
Note 2) The B
10
figure is estimated from SMC life tests. The B
10d
figure is
derived from B
10
using the assumption in ISO 13849-1:2008 Annex C.
Contact SMC for details.
2.2 Input/output characteristics
2.3
Operating principle
If a load is applied to the transmission plate B
①
, this force will be
transmitted to the shaft
③
via the transmission plate A
②
and the
diaphragm
④
and valve
⑤
will be pushed down.
As a result, part of the supply pressure will be output to the OUT side. The
output air pressure acts on the lower side of the diaphragm
④
, which
counteracts the force pushing down on the diaphragm by the load, this
becomes the set pressure. If the load decreases here, the diaphragm
④
will be pushed up by the output pressure and the valve
⑤
will close and
then the exhaust valve
⑥
will open.
As a result, the excess pressure on the OUT side will be released to
atmosphere. Thus the output pressure changes linearly by the load
applied.
Figure 2
Caution
Special products might have specifications different from those shown in
this section. Contact SMC for specific drawings. These drawings will give
the appropriate specification details and compliance with the safety
principles of ISO 13849, if applicable.
3 Installation
3.1 Installation
Warning
•
Do not install the product until the safety instructions have been read
and understood.
•
Install and remove any work piece when the supply pressure is applied.
•
If a load sensor fails and danger to the system can be predicted, install a
safety circuit in the system to avoid danger.
3 Installation - continued
•
Use the mounting hole (
φ
18.5) in the mounting bracket on top of the load
sensor to mount onto the cylinder head.
Use the screw
（
M22×1.5) on the transmission plate B at the bottom of
the load sensor to mount a jig to hang the work piece.
•
When mounting, take measures to prevent loosening at the mounting
screw section.
Figure 3
3.2 Operating environment
Warning
•
Do not use in an environment where corrosive gases, chemicals, salt
water or steam are present.
•
Do not use in an explosive atmosphere.
•
Do not expose to direct sunlight. Use a suitable protective cover.
•
Do not install in a location subject to vibration or impact. Check the
product specifications.
•
Do not mount in a location exposed to radiant heat.
3.3 Piping
Caution
•
Before piping make sure to clean up chips, cutting oil, dust etc.
•
When installing piping or fittings, ensure sealant material does not enter
inside the port. When using seal tape, leave 1.5 to 2 threads exposed on
the end of the pipe/fitting.
•
Tighten fittings to the specified tightening torque.
3.4 Air source
Caution
•
Install an air filter on the supply side near this product. Select filtration of
5
µ
m or less.
•
Compressed air containing a large amount of drain can cause this
product or other air compressor to malfunction. Install an after-cooler, air
drier or drain catch as countermeasures. Avoid using a lubricator.
•
A large amount of carbon powders generated from the compressor can
stick inside this product resulting in malfunction.
3.5 Operation
Caution
•
Do not use this load sensor outside the specifications because it can
cause a product failure.
3.6 Lubrication
Caution
SMC products have been lubricated for life at manufacture, and do not
require lubrication in service.
If a lubricant is used in the system, use turbine oil Class 1 (no additive),
ISO VG32. Once lubricant is used in the system, lubrication must be
continued because the original lubricant applied during manufacturing will
be washed away.
ORIGINAL INSTRUCTIONS
Caution
Caution indicates a hazard with a low level of risk
which, if not avoided, could result in minor or
moderate injury.
Warning
Warning indicates a hazard with a medium level of
risk which, if not avoided, could result in death or
serious injury.
Danger
Danger indicates a hazard with a high level of risk
which, if not avoided, will result in death or serious
injury.
③
Shaft
②
Transmission
plate
A
④
Diaphragm
⑥ E
xhaust
valve
①
Transmission
plate B
①
Transmission
plate B
Figure 1
Input/output characteristic
⑤ Valve
Load N
O
u
tp
u
t
p
re
s
s
u
re
M
P
a
②
Transmission
plate
A
