Rice Lake SURVIVOR ATV series, Assembly Instructions Manual

Page: 12 / 22

8 ATV Portable Truck Scale Assembly Instructions
Be certain each load cell grounding strap is securely
connected to the top plate and bottom plate of each
load cell mount. Some models have ground straps
i n c l u d e d t o i n s t a l l b e t w e e n m o d u l e s . T h e s e
inter-module straps ensure that the entire scale is
connected to the same single-point ground. There
should be metal-to-metal contact with no presence of
paint or grout. This strap is designed to channel power
surges on the deck around—rather than through—the
load cell to ground. A thick coating of anti-oxidant
g r e a s e s h o u l d b e m a i n t a i n e d o n a l l g r o u n d
connections to prevent corrosion. A separate grounding system conductor must extend
uninterrupted from the main service panel ground to
the scale to protect load cells and scale wiring from
lightning and other transient damage. This ground
wire conductor must be an unsheathed #10 copper
wire or larger. Run the bare ground wire conductor
intact from the AC power ground rod to the scale in a
separate trench.
Bring the wire up from the trench
near the J-box and attach it to the ground lug located
in the J-box pocket. This grounds the scale frame to
the same single-point ground as the AC power for the
indicator.
A ground wire is included to attach the J-box ground
lug to the ground lug located in the J-box pocket.
Grounding of the J-box is essential for operation of
the DC transient protection incorporated into the
J-box.
3.5 Installing Transient Protection
A two-year lightning protection package comes standard all truck scales. The individual components of this
comprehensive package are designed to protect AC and DC portions of the system. The lightning protection
package includes:
• DC transient protection included with standard J-box board(s). This DC transient protection handles up
to eight load cells. Scales with more than eight load cells require additional J-boxes.
• Self-contained DC transient protection unit in the homerun cable at the indicator.
• A 115 VAC uninterruptable power supply/surge protector in the AC line before the indicator.
• Number 10 bare ground conductor cable buried in earth from scale frame to DC transient board at
indicator and finally to the AC power ground lug.
Figure 3-2. Grounding and Transient Protection on ATV Scale
NOTE : Serial communications (if used) may also require transient protection to fully protect entire system. A TP-232 DC Transient
Protection is suitable protection for serial communications lines. In addition, printers, remote displays and other devices
connected to serial communications should be protected with AC transient protection.
10 ga. bare ground wire to DC
protection ground before indicator
Ground Lug
Located in
J-box Pocket