EXPLOSION-PROOF TYPE SINGLE POINT BEAM LOAD CELL
1. INTRODUCTION
LCB01/02 series are explosion-proof type single point beam load cells.
They are used to configure simplified weighing platforms for weigh-
ing, mixing and filling at a factory site handling flammables. Optimum
load cell performance is achieved through proper operation.
To install the load cell properly, the static conditions, as well as dy-
namic factors (i.e., shock and vibration) must be considered.
2. SPECIFICATIONS
Rated capacities .................................................................... 300,600,1500 N
Rated output....................................................................... 0.3059mV/V
10%
Maximum safe overload ............................................150% of rated capacity
Combined error ............................................................. 0.03% of rated output
Zero balance................................................................ 20
5% of rated output
Compensated temperature range.......................................................-10~40
Maximum excitation voltage ..................................................................... 15V
Input terminal resistance.................................................................. 418
20
Output terminal resistance .............................................................. 348.5 5
Insulation resistance .................................... Greater than 5000M at 50VDC
Temperature effect on zero ................................. 0.05% of rated output/ 10
Temperature effect on span .......................................... 0.03% of LOAD/ 10
Maximum permissible tare ...........................................33% of rated capacity
Cable length ........................................................................................
7 6m
Explosion-proof class ......................................Exd
BT4 (Japanese standard)
3. NOTES ON INSTALLATION
DANGER
This load cell is an explosion-proof type electrical device
and conforms to “Exd BT4” (Japanese standard). Install it
properly, or it may cause an explosion. Only those who
have an adequate knowledge of the installation of explo-
sion-proof type electrical devices are to be allowed to in-
stall it.
3-1 INSTALLING ON A BASE
(1) The base should be rigid to prevent it from slanting or curving under
normal operating conditions.
If the base yields, the platform will bend and adversely affect the load
cell.
(2) Use a highly rigid base. The mounting surface for the load cell re-
quires a surface finish of 25S (JIS*) or more.
*JIS=Japan Industrial Standard
(3) Use four hexagon socket head bolts (tensile strength Class 10.9-JIS
or equivalent) or high-tension hexagon head bolts (tensile strength
Class 10.9-JIS or equivalent) to mount the load cell on the base. Table
1 lists the applicable clamping torque and screw-in depth. Be sure to
avoid using ordinary bolts (of a lower tensile strength) available on
the market.
Table 1
(4) Tighten the bolts while holding the mounting side of the load cell.
If a base spacer is used, make sure that the attaching surface is
clean and free from foreign matter.
3-2 ATTACHING THE PLATFORM
(1) When the total platform weight with load is less than 150% of the
rated capacity, the load cell provides optimum performance. The total
load should be as light as possible to prolong the service life and
excellent performance of the load cell.
(2) Use a platform fixture with high rigidity. The mounting surface re-
quires a surface finish of 25S (JIS) or more.
(3) Use four hexagon socket head bolts (tensile strength Class 10.9-JIS or
equivalent) or high-tension hexagon head bolts (tensile strength Class
10.9-JIS or equivalent) to attach the platform fixture to the load cell.
Table 1 lists the applicable clamping torque and screw-in depth. Avoid
using ordinary bolts (of low tensile strength) available on the market.
If the platform fixture is made of aluminum or other non-rigid metals, use
a steel washer to disperse the compressive load applied by the bolts.
(4) Tighten the bolts so that unnecessary force (torsion or lateral load) is not
applied to the load cell.
Clean the attaching surfaces of the platform spacer, if used.
(5) For the allowable dimensions of the platform, see Figure 1. Also,
when designing a platform, see the "OVERLOAD PRECAUTIONS" on
the next page.
3-3 OVERLOAD PRECAUTIONS
(1) Mechanical strength of the load cell
When a load is applied to the center of the load cell, a load of less than
150% of the rated capacity will not cause any trouble.
However, the allowance range of the overload is reduced as the load-
ing point shifts from the center of the load cell. Therefore, the allowable
limit at the corner of the platform should be 100% of the rated
capacity.(See Figure 1 of corner position.)
Repeated overloading, exceeding the allowable limit, may shorten the
service life of the load cell, and may even destroy it in extreme cases.
This also applies to a lateral load.
(2) Overload stopper
If excessive shock is applied when positioning an object on the plat-
form, the load will exceed the allowable limit. Therefore, be sure to
attach an overload stopper for the load cell.(See Figure 2.)
Attach the overload stopper so that
the stopper comes into contact with
the load cell with as wide an area as
possible when the load of 150% of
the rated capacity (load plus weighing
platform) is applied to the center of the
load cell.
(3) Corner stopper
Although the overload stopper is prop-
erly adjusted, if an overload is applied
to the corners of the platform, it may
exceed the allowable limit due to the
flexibility of the base. Therefore, attach
corner stoppers to come in contact with
the platform at approximately 100% of
the rated capacity (See Figure 3.)
(4) If an overload or excessive shock force
is likely to occur, overlay the platform
with a shock absorber or select a load
cell with a rated capacity that is double
or triple the overall weight (the platform
weight plus the measurement weight).
3-4 CABLE COLOR CODE / TREMINAL TYPE
RED ............. EXC + ORANGE .............SENSE +
WHITE .......... EXC - BLACK ................SENSE -
GREEN ......... SIG + YELLOW .............SHIELD
BLUE ........... SIG -
TERMINAL TYPE....... 3 ROUND TERMINAL(V1.25-3)
4. MAINTENANCE
(1) Remove all dirt and dust from the load cell, and always use it in a clean
environment.
(2) When cleaning, do not wash off dirt and dust; use an air blower.
(3) Periodically inspect the overload stopper and corner stoppers.
5. DIMENSION
/
