Technical training seminars are available through Rice Lake Weighing Systems.
Course descriptions and dates can be viewed at www.ricelake.com/training
or obtained by calling 715-234-9171 and asking for the training department.
Rice Lake Weighing Systems is an ISO 9001 registered company.
November 19, 2014
i
Page 4
Rice Lake continually offers web-based video training on a growing selection
of product-related topics at no cost. Visit www.ricelake.com/webinars.
iiBenchmark HD Series
Page 5
1.0Introduction
DANGER
WARNING
CAUTION
Important
WARNING
This manual provides reference information to install and wire the Benchmark HD series single-point benchtop
scale which is shown in Figure 1-1.
Figure 1-1. Benchmark HD Series Bench Scale
This NTEP-approved bench scale is available in a 30" x 30" and 36" x 36" platform with capacities from 250 to
500 lbs. Both capacities come standard with a potted single point load cell that is environmentally sealed. It also
comes with a standard ten feet of load cell cable. The heavy duty capacity scale is constructed with a 304 stainless
steel cover and mild steel frame construction to withstand many years of rugged use.
1.1Safety
Safety Signal Definitions:
Indicates an imminently hazardous situation that, if not avoided, will result in death or serious
injury.
Indicates a potentially hazardous situation that, if not avoided could result in serious injury or
death, and includes hazards that are exposed when guards are removed.
Indicates a potentially hazardous situation that, if not avoided may result in minor or moderate
injury.
Indicates information about procedures that, if not observed, could result in damage to
equipment or corruption to and loss of data.
General Safety
Do not operate or work on this equipment unless you have read and understand instructions in the
manual. Failure to follow the instructions or heed the warnings could result in injury or death. Contact
any Rice Lake Weighing Systems dealer for replacement manuals. Proper care is your responsibility.
Failure to heed may result in serious injury or death.
DO NOT allow minors (children) or inexperienced persons to operate this unit.
DO NOT operate without all shields and guards in place.
DO NOT jump on the scale.
DO NOT use for purposes other then weight taking.
DO NOT place fingers into slots or possible pinch points.
DO NOT use any load bearing component that is worn beyond 5% of the original dimension.
DO NOT use this product if any of the components are cracked.
DO NOT exceed the rated load limit of the unit.
DO NOT make alterations or modifications to the unit.
DO NOT remove or obscure warning labels.
Keep hands, feet and loose clothing away from moving parts.
Introduction1
Page 6
1.2Benchmark HD Specifications
Table 1-1 lists the Benchmark HD model specifications.
Load Cell250 kg for 250 lb; 500 kg for 500 lb
Overload Protection5 point, independently adjusted
Cable Length10 ft (3 m) - 6 wire shielded
Output Impendance350
Maximum Overload200%
Compensated Temperature Range-10°C/14°F to +40°C/104°F
Dimensions/Capacities
SizeCapacityHeight
30" x 30"/762 mm x 762 mm250 lb/125 kg8.75"/222.25 mm
36" x 36"/914.4 mm x 914.4 mm250 lb/125 kg
Table 1-1. Benchmark HD Specifications
500 b/250 kg
500 lb/250 kg
2Benchmark HD Series
Page 7
2.0Installation
Benchmark HD Deck Cover
Bubble Level Location
The following sections explain the installation procedure for the Benchmark HD.
2.1Unpacking the Benchmark
Immediately after unpacking, visually inspect the Benchmark HD to ensure that the unit is undamaged. The
shipping carton should contain the bench scale and this manual. If the scale was damaged in shipment, notify Rice
Lake Weighing Systems and the shipper immediately.
2.1.1Leveling the Scale
Place the scale in the desired location. Lift off the deck cover and locate the bubble level (see Figure 2-1).
Figure 2-1. Top Plate Removed Showing Bubble Level Location
Adjust the four corner feet until the scale is level and all feet contact the support surface, so that the scale does not
rock. Lock the jam nuts on the feet when the final level is correct.
2.2Connecting the Load Cell Cable
The Benchmark HD comes with a standard 10 feet of color-coded load cell cable. Do not cut this cable. The load
cell is temperature compensated for an exact length of 10 feet.
See your indicator manual to determine the proper load cell cable input connectors. Use the following color codes
to wire the load cell cable. Once complete, install the top cover for the bench scale back onto the scale.
6-Wire Color CodeFunction
Red+ Signal
White- Signal
Green+ Excitation
Grey- Excitation
Blue+ Sense
Brown- Sense
Yellow Shield
Table 2-1. Load Cell Wiring
Installation3
Page 8
2.3Grounding the Scale Base
Bench scales can build up static electricity charge during weighing operations. If powerful enough, this charge can
travel through the load cell cable to the indicator. To prevent this, all bench scales should be adequately grounded
so that static charges and transient electrical surges can drain directly to the ground. A recommended practice is to
connect the scale base to an AC ground circuit using at least #12 wire. All Benchmark series scales have either a
grounding screw or a hole for such a grounding screw located on the bottom of the lower frame for this purpose.
4Benchmark HD Series
Page 9
3.0Calibration
It is recommended that the scale be “exercised” by loading it to near capacity two or three times before calibration
to be certain that everything is seated. To calibrate the Benchmark HD scale place test weights on the scale
platform equal to 70 - 100% of the scale’s capacity. If several weights are used, distribute them evenly around the
platform.
See your indicator manual for specific indicator calibration procedures.
Calibration5
Page 10
4.0Troubleshooting
SymptomProbable Cause Remedy
No displayPower disconnectedConnect power
Cable cut or disconnectedRepair cable
Signal leads incorrectly wired at indicator Connect according to indicator manual
Display stays at zeroIncorrect load cell cable connectionsConnect according to manual
Faulty indicatorService the indicator
Erratic weight displayVibration near the scaleRemove the source of vibration, or
adjust the digital averaging of the
indicator to minimize the erratic display
Scale is not levelLevel the scale
Water damage to the load cell or load
cell cable
Faulty indicatorService the indicator
Loose load cell screwsTighten the correct torque
Faulty load cellTest and replace if necessary
Consistently low weightsIndicator is not properly adjusted to zero Zero the indicator correctly
Scale deck cover is bindingObtain adequate clearance
Overload stops set too highReset overload stops correctly
Indicator not calibrated for scaleCalibrate
Faulty load cellTest and replace if necessary
Replace the load cell
Table 4-1. Troubleshooting Guide
6Benchmark HD Series
Page 11
5.0Replacement Parts
4DBMFGPPU
)FYKBNOVU
0WFSMPBEQSPUFDUJPO
-PBEDFMMTDSFXT
0WFSMPBETDSFXTUPQT
-FWFMCVCCMF
-PBEDFMMTDSFXT
5.1Load Cell Replacement
Use the following steps to replace load cells.
Figure 5-1. 30'' x 30'' or 36'' by 36'' Load Cell Mount
1. Unplug AC power from the indicator and disconnect the load cell cable from the indicator.
2. Lift off the scale top cover and locate the four upper load cell screws. Use a 1/2" wrench to unscrew and
remove those four load cell screws. Refer to Figure 5-1 for their location.
3. Lift off the scale’s top frame.
4. Remove the spacer between the load plate and load cell and set it aside.
5. Loosen the four overload stop screws and turn each screw in one turn to provide ample clearance for the
new load cell.
6. Turn the scale over and back off the overload protection screw one complete turn to provide clearance.
7. Unscrew and remove the lower load cell screws.
8. Remove the bottom shim beneath of the load cell and set it aside.
9. Remove the load cell and cable from the scale.
10. Position the bottom shim directly beneath the load cell and screw in the lower load cell screws. NOTE:
Torque bolts to 200 in-lbs.
11. Turn the scale upright. Position the spacer plate on the load cell, then place the top frame into position.
12. Screw in the four upper load cell screws. NOTE: Torque bolts to 200 in-lbs.
13. Connect the load cell cable to the indicator.
14. Recalibrate the scale as described in Section 3.0 on page 3 of this manual.
15. Adjust the load cell overload protection screws on the bottom of the scale by loading the scale to 125%
capacity. Place this weight on the top cover, centered on the platform. Use a hex wrench to screw in the
load cell overload protection screw until it touches the load cell, the back off 1/6 turn.
16. Recheck calibration.
17. To reset corner overload stop screws, load the top spider over one corner with approximately 30% of scale
capacity.
18. Adjust the screw under that corner to just touch the top frame.
19. Place a drop of a non-permanent, high-strength locking compound such as Loctite
20. Back screw off slightly so it is not touching the top frame.
21. Repeat for each corner.
22. Replace the top cover and re-level the scale if necessary.
®
on the thread.
Loctite is a registered trademark of Henkel Corporation, U.S.A.
Replacement Parts7
Page 12
5.2Replacement Parts
Figure 5-2. Benchmark HD Assembly Drawing Breakout
8Benchmark HD Series
Page 13
The following replacement parts are available for the Benchmark HD Series scale, PN’s 93414, 93415, 93416, and
93417.
Item #DescriptionRLWS Part NumberQty.
1
2 & 16
3 & 15
4
5
6
7
8
9
10
11
12
13
14
Top cover93775 - 30" x 30"
93768 - 36" x 36"
Screw cap, 5/16 - 18NC x 3249788
Lock washer, 5/16 regular15153
Top frame93758 - 30" x 30"
93760 - 36" x 36"
Self adhesive bumper 26407
Shim, 3/16 x 2 - 3/8 x 3 SST87358
Load cell91690 - 250 lb scale
91692 - 500 lb scale
Bottom frame93759
Hex head bolt, 3/8 - 16NC x 114742
Hex jam nut, 3/8 - 16NC14649
Bench scale foot74585
Set screw, 1/2 - 20NF x 3/4 15051
Bubble level15410
Label roll52342
1
8
8
1
30/36
2
1
1
4
4
4
1
1
1
Table 5-1. Replacement Parts
Replacement Parts9
Page 14
Benchmark Series Limited Warranty
Rice Lake Weighing Systems (RLWS) warrants that all RLWS equipment and systems properly installed by a
Distributor or Original Equipment Manufacturer (OEM) will operate per written specifications as confirmed by the
Distributor/OEM and accepted by RLWS. All systems and components are warranted against defects in materials
and workmanship for two years.
RLWS warrants that the equipment sold hereunder will conform to the current written specifications authorized by
RLWS. RLWS warrants the equipment against faulty workmanship and defective materials. If any equipment fails
to conform to these warranties, RLWS will, at its option, repair or replace such goods returned within the warranty
period subject to the following conditions:
•Upon discovery by Buyer of such nonconformity, RLWS will be given prompt written notice with a
detailed explanation of the alleged deficiencies.
•Individual electronic components returned to RLWS for warranty purposes must be packaged to
prevent electrostatic discharge (ESD) damage in shipment. Packaging requirements are listed in a
publication, Protecting Your Components From Static Damage in Shipment, available from RLWS
Equipment Return Department.
•Examination of such equipment by RLWS confirms that the nonconformity actually exists, and was
not caused by accident, misuse, neglect, alteration, improper installation, improper repair or improper
testing; RLWS shall be the sole judge of all alleged non-conformities.
•Such equipment has not been modified, altered, or changed by any person other than RLWS or its duly
authorized repair agents.
•RLWS will have a reasonable time to repair or replace the defective equipment. Buyer is responsible
for shipping charges both ways.
•In no event will RLWS be responsible for travel time or on-location repairs, including assembly or
disassembly of equipment, nor will RLWS be liable for the cost of any repairs made by others.