Rice Lake RL1900 Series - Manual (Page 5)

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5. Load cells should not be installed in the mounts until all welding is completed.
The heat generated from welding current passing through a load cell can
damage the adhesive holding the strain gauge to the body. If possible, use a
dummy load cell when welding to maintain finished height. If welding is
unavoidable after load cell installation, ground in such a manner as to prevent
welding current from passing through the load cell. Ground the welder as
closely as possible to the point of welding. Never rely on check rods or piping
for grounding.
6. When possible, use only “hermetically sealed” load cells in washdown appli-
cations. “Environmentally protected” load cells are not suitable for such
applications and will be damaged. If tanks and surrounding equipment are
frequently steam cleaned, or if the load cell is subjected to direct washdown, a
protective shroud for the weighing assembly is recommended. Proper drainage
is necessary so the weighing assembly is not standing in water.
7. Detailed instructions for installing this load cell mount follow. When installing
the load cells, use the bolts provided or grade 5 or stronger hardened bolts. Pay
particular attention to the recommended torque values. Some mounts require
very loosely torqued bolts to allow the load cells to flex easily. Others must be
very tight to prevent the load cells from creeping or digging into the mount.
2.2 Installing the RL1900 Mount
The type of installation, structure of the vessel supports, and strength of the
mounting surface determines the method of locating, attaching, and assembling the
RL1900 Mounting Assembly. Carefully consider three areas that commonly cause
accuracy problems:
• Are the supporting legs adequately braced so they will not spread when the
system is fully loaded?
• Does the supporting structure have the necessary strength to prevent flexing
when the system is fully loaded?
• Is there attached equipment such as skirting, venting, or piping which is likely
to cause binding or lack of flexibility?
LOCK WASHER
TOP PLATE
NYLON LOCK NUT
SHOULDER BOLT
CONCAVE WASHER
LOAD CELL
MOUNTING BLOCK
UPPER SUPPORT
MOUNTING BLOCK
HEX HEAD LOADING BOLT
CONVEX WASHER
FLAT WASHER
BASE PLATE
LOAD CELL BOLT
LOAD CELL
CONCAVE WASHER
CONVEX WASHER