SR Instruments SR Scales SR555i Service manual

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 1 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
S
by SInstruments, Inc.
Operating and Service
Manual
Model SR555i
Stand-On Scale System

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 2 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
TABLE OF CONTENTS
TABLE OF FIGURES......................................................................................................................2
PACKING CHECKLIST.................................................................................................................3
ASSEMBLY.......................................................................................................................................4
REPLACEMENT PARTS AND ACCESSORIES ........................................................................7
SYSTEM DESCRIPTION AND INTENDED USE.......................................................................7
MICROBAN ANTIMICROBIAL PROTECTION.......................................................................8
STORAGE AND TRANSPORTATION ........................................................................................8
CLEANING AND DISINFECTING...............................................................................................9
SPECIFICATIONS.........................................................................................................................10
BUTTON FUNCTIONS.................................................................................................................11
BASIC SYSTEM OPERATION....................................................................................................12
BATTERY REPLACEMENT.......................................................................................................14
THEORY OF OPERATION .........................................................................................................15
CALIBRATION..............................................................................................................................16
CONFIGURING SEND BUTTON................................................................................................18
TROUBLESHOOTING.................................................................................................................19
WARRANTY...................................................................................................................................20
NOTES.............................................................................................................................................21
TABLE OF FIGURES
Figure 1: Assembly Diagram ..........................................................................................................4
Figure 2: Cable Clamp and Display Cable Connector.................................................................5
Figure 3: Battery Compartment Cover .........................................................................................5
Figure 4: Handrail/Height Bar Diagram.......................................................................................6
Figure 5: Printer Mounting Collar.................................................................................................6
Figure 6: Printer Mounting Bracket..............................................................................................6
Figure 7: Button Display...............................................................................................................11
Figure 8: Bottom of Scale Base.....................................................................................................14
Figure 9: Calibration Tolerance Table........................................................................................16
Figure 10: Calibration Switch Diagram ......................................................................................16

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 3 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
PACKING CHECKLIST
SR555iStand-On Scale

DESCRIPTION
QUANTITY
Box 1
BASE ASSEMBLY (FIVE (5) SET SCREWS IN PLACE)
1 ea
MAST
1 ea
DISPLAY UNIT WITH CABLE (FIVE (5) SET SCREWS IN PLACE)
1 ea
PACKAGE OF SIX (6) “C” CELL BATTERIES
1 ea
MEDICAL GRADE AC POWER SUPPLY (SR555i-AC ONLY)
1 ea
LOCTITE
1 ea
1/8” ALLEN WRENCH
1 ea
QC INSPECTION SHEET
1 ea
CALIBRATION CERTIFICATE
1 ea
WARRANTY CARD
1 ea
MANUAL
1 ea
Box 2 Optional Handrail and/or Optional Height Bar
OPTIONAL HANDRAIL SET WITH HARDWARE
1 ea
OPTIONAL HEIGHT BAR
1 ea
Box 3 SR8219 Optional Printer Kit
PRINTER
1 ea
PRINTER BATTERY CHARGER
1 ea
PRINTER CABLE
1 ea
PRINTER MOUNTING COLLAR& HARDWARE
1 ea
PRINTER MOUNTING BRACKET & HARDWARE
1 ea
PRINTER PAPER
1 ea
LOCTITE
1 ea

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 4 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
ASSEMBLY
STEP 1: Unpack the scale system and check
parts against the PACKING CHECKLIST. If
there are any missing or damaged parts, please
call the service hotline at 1-800-654-6360.
STEP 2: (Figure 1) Verify that the serial number
on the Display Unit (1) matches that on the Base
Assembly (2).
STEP 3: Remove the four (4) set screws from
Base Assembly collar and apply a small amount
of Loctiteto each. Insert Mast (3) into Base
Assembly collar and seat firmly. Re-install set
screws in Base Assembly collar and tighten
securely.
NOTE: If an optional printer has been ordered,
go to Page 6 “INSTALLING OPTIONAL
PRINTER” before proceeding.
STEP 4: Feed the display cable down through
the Mast and pull out through the Base
Assembly.
STEP 5: Remove the set screws from the
Display Unit collar. Set the Display Unit
squarely on top of the Mast with the display
label facing the scale platform. Apply a small
amount of Loctiteto the four (4) set screws
and reinstall the set screws, tightening securely.
#
PART NAME
1
Display Unit
2
Base Assembly
3
Mast
4
Cable Clamp
5
Display Cable Connector
6
Handrails (optional)
7
Height Bar (optional)
8
Battery Compartment
9
Printer (optional)
10
Printer Cable (optional)
11
Printer Mounting Collar (optional)
12
AC Power Supply
Figure 1: Assembly Diagram
Continued next page
7
1
2
3
6
8
9
12

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 5 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
ASSEMBLY (Cont’d)
STEP 6: (Figure 2) Lay the system on its side
and remove the Cable Clamp (4) from the Base
Assembly. Attach the Display Cable Connector
(5) to its mate from the Base Assembly.
STEP 7: (Figure 2) IMPORTANT: Reinstall the
Cable Clamp! Slide the cable back up into the
Mast. Set the display cable into the groove under
the Cable Clamp and reinstall the Cable Clamp,
leaving just enough slack to alleviate any tension
on the Cable exiting the Platform. Securely
tighten the Cable Clamp screw. Excess cable
MUST NOT contact the floor.
STEP 8: (Figure 3) Open the Battery Compartment cover
and install the six (6) supplied “C” cell batteries as
indicated on the cover diagram. Close the cover and
tighten thumb screw.
STEP 9: Return the scale to the upright position.
INSTALLING AC POWER SUPPLY (SR555i-AC):
STEP 10: Connect AC Power Supply (12) to the bottom
side of the Display Unit and plug into standard AC Wall
outlet.
STEP 11: Press and hold “ZERO/WEIGH” button to set
System Zero (see directions for SETTING SYSTEM
ZERO).
Figure 2: Cable Clamp and Display Cable
Connector
Figure 3: Battery Compartment
Cover
Continued next page
4
5

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 6 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
ASSEMBLY (Cont’d)
INSTALLING OPTIONAL HANDRAILS
STEP 1: (Figure 4) Attach top of each of the Handrails (6) to the bottom right and left of the
Display Unit (1). Use two (2) screws and two (2) split-lock washers on each side; slightly tighten.
(Do not tighten all of the way.)
STEP 2: Attach the bottom of the Handrails to the right and left side of the Base Assembly (2)
using one (1) screw and one (1) split-lock washer for each handrail. Tighten all six (6) screws
securely.
INSTALLING OPTIONAL HEIGHT BAR
STEP 1: (Figure 4) Remove the set screw on the back
of the Display Unit (1) and in the Base Assembly (2).
STEP 2: Slide the Height Bar (7) down through the
hole in the Display Unit and seat firmly into the Base
Assembly. Apply a small amount of Loctiteto the two
(2) set screws and reinstall, tightening securely.
INSTALLING OPTIONAL PRINTER
STEP 1: (Figure 4) Slide the Printer Mounting Collar
(11) over the Mast (3). Position the Printer Mounting
Collar approximately 5 inches from the top of the mast.
Tighten the two (2) set screws to secure the Printer
Mounting Collar to the Mast. NOTE: The three (3)
holes on the Printer Mounting Collar should be towards
the top of the Mast (Figure 5).
Figure 4: Handrail/Height
Bar Diagram
Figure 5: Printer Mounting
Collar
Figure 6: Printer Mounting
Bracket
3
7
11
1
2
6
10
9
Continued next page

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 7 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
ASSEMBLY (Cont’d)
STEP 2: Apply a small amount of Loctiteto the two small screws and attached the Printer
Mounting Bracket to the Printer Mounting Collar. (Figure 6).
STEP 3: Attach the Printer to the Printer Mounting Bracket.
STEP 4: After the Display Unit (1) is installed, refer to page 4, plug the Printer Cable (10) into
the Printer and into the connector on the bottom of the Display Unit; tighten Printer Cable screws.
REPLACEMENT PARTS and ACCESSORIES
SYSTEM DESCRIPTION and INTENDED USE
SYSTEM DESCRIPTION
The SR555iStand-On Scale System employs the latest in microprocessor and load cell technology
to provide accurate and repeatable weight data. Four (4) identically matched transducers are
strategically placed to ensure an accurate representation of the patient’s weight.
The low power microprocessor circuitry allows the SR555ito derive its power from six (6)
common “C” cell batteries that will provide up to 10,000 weight readings before needing
replacement. This eliminates the need for an external battery charger.
The SR555ican be powered by a Medical Grade AC wall power supply, with the “C” cell
batteries providing backup power. Continuous wall power allows the unit to be always on and
ready to take weight readings without the need to make contact with the membrane switch.
The patient’s weight is displayed on a 16-character dot matrix LCD. The weight data may be
viewed, in either pounds or kilograms, with a displayed resolution of 0.1 for each.
Part #
Description
FRGSM06U09P1J
Medical Grade AC Power Supply
SR3070
Handrail Set with assembly hardware
SR3086MB
Height Bar: Extends from 43 in to 79 in (109 cm to 201 cm)
SR8219
Printer Kit (optional; contains all printer parts listed below)
FRAP1300
Printer
FRAP1300BR-01
Printer Mounting Bracket
SE8294
Printer Cable
FRAP1300BP01
Rechargeable Battery Pack
FRTP130012C
Paper, thermal printer 58mm (10 rolls)
FRBC1300
Printer Battery Charger
MF8209
Printer Mounting Collar
Continued next page

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 8 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
SYSTEM DESCRIPTION and INTENDED USE (Cont’d)
INTENDED USE
The SR555iStand-On Scale System is specifically
designed for use as a stand-on scale for weighing
ambulatory patients. Optional equipment includes a
Handrail Set, Height Bar, Printer and AC Power
Supply. SR555iStand-On Scale System is a preferred
means of gathering patient weight data of ambulatory
patients weighing up to 1000 pounds or 454 kilograms.
MICROBAN ANTIMICROBIAL PROTECTION
Microban® antimicrobial technology has been added to help reduce the growth of bacteria as part
of a medical center's approach to creating a cleaner healthcare environment. For more information,
visit https://www.microban.com/sr-scales
STORAGE and TRANSPORTATION
STORAGE
If storing this equipment for periods longer than three (3) months, remove the batteries. To
maintain proper operation of this instrumentation, storage and transport conditions should not vary
outside the following conditions: Relative Humidity 0% to 85%, Ambient Temperature 14F to
122F(-10C to +50C).
TRANSPORTATION
To transport the SR555i, lower the Height Bar, if included, tilt the scale back and wheel to the new
location. Lower the platform back down to the floor being careful not to shock the scale.
WARNING
HAND RAIL IS INTENDED TO
HELP STABLIZE AN
AMBULATORY PATIENT.
DO NOT USE HAND RAIL AS A
LIFTING AID OR TO ASSIST IN
SUPPORTING A PATIENT.
HAND RAIL WILL NOT
PREVENT A FALL
WARNING
DO NOT EXCEED
MAXIMUM WEIGHT LIMIT OF
1000 LB / 454 KG

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 9 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
CLEANING and DISINFECTING
CLEANING
To clean the display / user interface and other scale contact areas:
Use a soft cloth dampened with water and mild detergent to clean scale surfaces.
Wipe surface with clean soft cloth dampened with water and then dry with clean soft cloth.
Do not use abrasive materials to clean scale surface to prevent damage to the surface
finish.
Do not spray liquid directly onto scale surfaces. Use only a damp cloth.
DISINFECTION
To disinfect the display / user interface and other scale contact areas:
Use a soft cloth dampened with disinfectant or a damp disposable disinfectant cloth. Cloth
cannot be dripping wet. Follow manufacturer’s instruction on the proper use of
commercially available disinfectants.
Disinfectant solutions with 1% sodium hypochlorite or 70% isopropyl alcohol are suitable
for display / user interface and other scale contact surfaces.
After disinfecting, use a soft cloth dampened with clean water and dry with a soft clean
cloth to prevent buildup of material on scale finish.
Do not use abrasive material to disinfect / clean scale surfaces to prevent damage to the
surface finish.
Do not spray liquid directly onto scale surfaces. Use only a damp cloth.
WARNING: DO NOT SPRAY CLEANING SOLUTION OR LIQUIDS DIRECTLY
ON SURFACES TO BE CLEANED.
WARNING: EXPOSURE TO EXCESSIVE LIQUID WILL DAMAGE USER
INTERFACE KEYPAD.
WARNING: DO NOT USE PRESSURIZED WATER OR STEAM. THE SCALE
SYSTEM CONTAINS ELECTRONIC COMPONENTS THAT MAY BE
ADVERSELY AFFECTED BY EXPOSURE TO SUCH AN
ENVIRONMENT.

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 10 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
SPECIFICATIONS
MAXIMUM WEIGHT CAPACITY
1000 lb or 454 kg
PLATFORM SIZE
15 3/4 in x 18 1/2 in (40 cm x 47 cm)
DISPLAY TYPE
16-Character Dot-Matrix LCD
DISPLAY RESOLUTION
0.1 lb / 0.1 kg
ACCURACY
0.1% +/- 1 digit of displayed resolution for calibrated
range
AUTO ZERO
One button operation
AUTO POWER DOWN
Approximately 30 seconds (adjustable to 300 seconds)
ENTER
Stores displayed reading in memory
RECALL
Recalls last stored stable weight, height, and BMI
AVERAGING
Automatic digital filter
POWER SUPPLY
Six (6) “C” cell batteries
Medical Grade AC Wall Power Supply
CALIBRATION
Calibration is traceable to NIST standards.
OPERATING CONDITIONS
Normal operating conditions for this product:
Ambient Temperature Range: 68F to 85F (20C to
30C) Relative Humidity Range: 0%-85%
Avoid exposure to high-pressure water or steam.
TRANSPORTATION and
STORAGE
Storage and transportation conditions should not vary
outside the following conditions: Relative Humidity
0% to 85%, Ambient Temperature 14F to 122F
(-10C to +50C). Remove batteries if storing longer
than three (3) months.

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 11 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
BUTTON FUNCTIONS
ZERO / WEIGH
Press and hold to zero. The display will read “WT = 0.0 Lb”. This is used to zero the
system before placing the patient on the scale system. This action also resets previously
stored weight, height and BMI values to zero. Ensure that nothing is in contact with the
weighing surface during this procedure.
Press to weigh. Weight stable indicator “” flashes then remains solid when stable. Auto
stores stable weight in memory.
SEND (PRINTER / EHR)
Press to send stored values to EHR or to printer. Output values include time, date, weight,
height, and BMI. Also, indicated on display when paper is out, “PAPER OUT” and when
door is open, “PAPER DOOR OPEN”.
RECALL
Press to recall the last stable weight. Display will scroll thru “WT”, “HT”, and “BMI”
stored values in approximately two second intervals.
ENTER
Press to save height data and display BMI calculation. Stable weight, height and BMI
values are stored in memory until next stable weight is stored or until system is zeroed.
BMI
Press to calculate the BMI. When the “BMI”is pressed, the default starting value “HT =
65 in”or “HT = 165 cm” is displayed. If there is no stored stable weight, the display will
indicate “NO WEIGHT DATA” and then go back to the weigh screen “WT = 0.0 Lb”.
Figure 7: Button Display
Continued next page

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 12 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
BUTTON FUNCTIONS (Cont’d)
MENU
Press Menu to edit setup.
Setting the UNITS: Use UP or DOWN arrow buttons to select “Lb” or “Kg”. Press
ENTER to save changes.
Setting ON TIME: Use UP or DOWN arrow buttons to adjust the “ON TIME”. The
“ON TIME” may be set from 30 to 300 seconds in 30 second increments. Press ENTER
to save changes.
Setting TIME and DATE: Use the UP arrow button to select digit. To change digit use
the DOWN arrow button. Press ENTER to save changes.
NOTE: When selected, the year position defaults to “00”
Configuring scale output: Use the UP or DOWN arrow buttons to select between PRINT
and EHR. Press ENTER to save changes.
Setting printout orientation: Use the UP or DOWN arrow buttons to select between
“PRINT INVERTED” and “PRINT NORMAL”. Press ENTER to save changes.
UP
Press UP to adjust height up from the default, to increase the scale’s “on time”, or to
select a digit when setting time and date.
DOWN
Press DOWN to adjust the height down from the default, to decrease the scale’s “on
time”, or to change the value of a selected digit when setting time and date.
BASIC SYSTEM OPERATION
SETTING SYSTEM ZERO
Make sure the scale is free and clear of any obstructions and press and hold the ZERO /
WEIGH button. The displayed message will indicate “HOLD TO ZERO”and count
down to zero. Make sure that nothing is in contact with the scale while zeroing the system.
In a few seconds, the display will read “WT = 0.0 Lb”(or Kg). This action also resets
previously stored weight, height, and BMI values to zero.
When using AC Power Supply: The scale requires only an initial setting of System Zero,
or any time the display reads “PLEASE ZERO”. The scale will otherwise zero track and
remove any slight fluctuations.
When using batteries for power: It is recommended that the system be zeroed prior to
each use.
Continued next page

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 13 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
BASIC SYSTEM OPERATION (Cont’d)
WEIGHING
When using AC Power Supply: Position the patient on the scale.
When using batteries for power: Position the patient on the scale and press the
ZERO/WEIGH button.
The weight stable indicator “” flashes on the display. When the weight is stable, the
weight stable indicator remains solid. The display will indicate the patient’s weight in
either pounds or kilograms; example: “WT = 123.5 Lb”. The stable weight is auto stored
in memory.
NOTE: If patient will be using a cane for support on the scale, place the cane on the scale
while zeroing the system. This will ensure that the patient’s NET weight will be displayed.
CALCULATING BMI
Press to calculate BMI.
When the BMI button is pressed, the default starting value is set either to 65 in or to 165
cm; example: “HT = 65 in”.Use the UP or DOWN arrows to adjust the default height to
the value of the patient’s height.
NOTE: To calculate the BMI, a patient’s stable weight needs be stored as indicated in
“WEIGHING” above, if no stable weight has not been stored “NO WEIGHT DATA”
will be displayed and the display will then go back to the weigh screen “WT = 0.0 Lb”.
Press ENTER to save height data and display BMI calculation. The BMI will be
displayed; example: “BMI = 20.5”.
RECALLING LAST STABLE WEIGHT
Press to recall last stable weight.
The display will scroll thru “WT”, “HT”, and “BMI” stored values in approximately two
second intervals; example: “RCL WT = 123.5 Lb”, “RCL HT = 65 in” and “RCL BMI
= 20.5”.

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 14 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
BATTERY REPLACEMENT
STEP 1: The display will read “REPLACE BATTERIES”.
STEP 2: (Figure 8) Place the scale on its side and open the battery compartment cover located in
the bottom of the scale base.
STEP 3: Remove and replace ALL six (6) “C” cell batteries. Refer to diagram on the battery
compartment cover for placement.
STEP 4: Press the “WEIGH” button to confirm display is working.
STEP 5: Tightly close the cover.
STEP 6: Zero the system.
Figure 8: Bottom of Scale Base
WARNING
DO NOT remove batteries while scale is on.
Allow scale to shut down naturally thru
timing out. This prevents possible voltage
drain on the printed circuit board coin
battery.

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 15 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
THEORY OF OPERATION
SR Instruments patient weighing systems are digital scales. Strain-gauge force cells convert the
force of an applied weight into an analog signal. This signal is amplified by an operational
amplifier and converted to a digital signal by an on-chip analog to digital converter. The digital
signal is filtered, converted to appropriate units, and displayed on the liquid crystal display.
Strain-gauge force cells each contain four strain gauges mounted in a full Wheatstone-bridge
configuration. These bridges convert the physical movement of the force cell, due to the applied
mass on the system, into minute changes in electrical resistance. These changes in resistance
produce a voltage difference across the Wheatstone-bridge, which is amplified by the operational
amplifier. The amplifier is configured to current sum the output of each cell, with potentiometers
serving to normalize the sensitivity (voltage out per unit of weight applied) of each bridge. The
offset potentiometer produces a small current, which nulls the output of the amplifier for an
unloaded system.
The output of the operational amplifier is digitized by the analog to digital converter. The sigma-
delta converter sums a rapid sequence of 0's (0 volts) and 1's(reference voltage) to achieve balance
with the input signal from the amplifier.
The micro-controller filters the digital output of the analog to digital converter, subtracts the value
saved during the system zero operation and scales the filtered output, and then displays the result
on the liquid crystal display. The micro-controller performs a moving-median filter of data for
continuous weigh and, for AutoHold; the micro-controller performs checks for signal stability
before locking in on the reading. If the data variance is greater than 0.1% in the AutoHold mode,
the micro-controller will reset the filter and start a new filtering period.
The micro-controller can be placed in a calibration mode, where the system can be re-calibrated.
In the calibration mode, the system slope is calculated from two points (zero and full scale) in the
2-point calibration mode or the slope and change in slope is calculated from three points (zero,
half, and full scale) in the 3-point calibration mode.

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 16 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
LOW
LIMIT
APPLIED
LOAD
HIGH
LIMIT
99.9 100.0 100.1
199.8 200.0 200.2
299.7 300.0 300.3
399.6 400.0 400.4
499.5 500.0 500.5
599.4 600.0 600.6
699.3 700.0 700.7
799.2 800.0 800.8
899.1 900.0 900.9
999.0 1000.0 1001.0
CALIBRATION
TOLERANCE TABLE
CALIBRATION
NOTE: Ensure that nothing is in contact with the scale system during this procedure. Remove
hands from the system when noting the displayed calibration results.
CHECKING CALIBRATION
STEP 1: Select known calibrated weights, traceable to NIST.
NOTE: The weights should total at least 500 pounds (half of the
maximum scale capacity). Put aside a subset of weight that is less than
half of the combined weight. DO NOT USE barbells or uncalibrated
weights.
STEP 2: Zero the scale by pressing and holding ZERO / WEIGH
button.
STEP 3: Place the subset of calibrated weight on the scale. Wait for
scale to stabilize; note scale reading.
STEP 4: Place all of the calibrated weight on scale. Wait for scale to
stabilize; note scale reading. Remove weight.
STEP 5: The scale readings should be within the Calibration Tolerance
Table (Figure 9).
Figure 9: Calibration
Tolerance Table
Figure 10: Calibration Switch Diagram
IMPORTANT
CALIBRATION Qualified service personnel only should perform this procedure. The
SR555iload cells have no user serviceable components and should not be tampered with
for any reason. Re-calibration is generally not required, but should be verified
periodically to ensure accuracy. The recommendation for calibration check is at least
once every 12 months, or as individual maintenance policy requires.
CALIBRATION SWITCH
Continued next page

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 17 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
CALIBRATION (Cont’d)
SETTING CALIBRATION
NOTE: Ensure that nothing is in contact with the scale system during this procedure. Remove
hands from the system when noting the displayed calibration results.
STEP 1: Remove the four (4) screws on the bottom of the display housing. Lift the display
panel. Put the scale system into the Calibration Mode by switching the calibration switch on the
display board (Figure 10). “CALIBRATION” will flash on the display.
STEP 2: Select known calibrated weights, traceable to NIST.
NOTE: The weights should total at least 500 pounds (half of the maximum scale capacity). Put
aside a subset of weight that is less than half of the combined weight. DO NOT USE barbells or
uncalibrated weights.
STEP 3: Press the MENU button until “FULL = 1000.00 Lb” is displayed. Change “FULL”to the
value of the total weight of the calibrated weights. Use the UP arrow button to select the digit and the
DOWN arrow button to change digit. Press ENTER to save changes.
STEP 4: Press the MENU button until “HALF = 500.00 Lb” is displayed. Change “HALF”to
the value of the subset of the selected calibrated weights. Use the UP arrow button to select the
digit and the DOWN arrow button to change the digit. Press ENTER to save changes.
STEP 5: Press MENU button until “3 Pt Calibration” is displayed. Press the UP arrow button.
STEP 6: Zero the scale by removing all weight from the platform. Press the UP arrow button.
STEP 7: Place the HALF weight from Step 4 on platform. Allow weight to stabilize. Press UP
arrow to save change.
STEP 8: Place the FULL weight from Step 3 on platform. Allow weight to stabilize. Press UP
arrow to save change.
STEP 9: Press ENTER to save the calibration, or WEIGH to exit without saving.
STEP 10: Remove weight and switch the scale system out of the Calibration Mode on the display
board (Figure 10).
STEP 11: Place the display panel into the display housing. Align the display panel with the four
holes in the display housing. Secure display panel with the four (4) mounting screws.
CAUTION
The integrated circuits and semiconductors on
the printed circuit boards may be damaged
by electrostatic discharge (ESD). Be sure to
use proper handling precautions at all times.

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 18 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
CONFIGURING SEND BUTTON
STEP 1: Remove the four (4) screws on the bottom of the display housing. Lift the display
panel. Put the scale system into the Calibration Mode by switching the calibration switch on the
display board (Figure 10). “CALIBRATION” will flash on the display.
STEP 2: Press the “MENU” key until “DATA OUT = PRINT” is displayed
STEP 3: Press “UP” or “DOWN” key to select between “EHR” and “PRINT”
STEP 4: Press the “ENTER” key to save
STEP 5: Switch the scale system out of the Calibration Mode on the display board (Figure 10).
STEP 6: Place the display panel into the display housing. Align the display panel with the four
holes in the display housing. Secure display panel with the four (4) mounting screws.
EHR OUTPUT
Electronic Medical Records (EMR) / Electronic Health Records (EHR) technology is supported by
the i-series scales from SR Instruments. The EMR/ EHR software is not included with scale.
There are many different EMR/ EHR software available and the connectivity of the scale to the
software requires the services of a professional.
A null modem cable is required to communicate with the scale.
Scale output when send button is configured to Electronic Health Records is as follows:
<esc>R<esc>Wnnn.n<esc>Hmmm.m<esc>Bkk.k<esc>Uuu<esc>E
Where:R is read
W is weight
nnn.n is the weight in Lb or kg
H is height
mmm.m is the height in inches or cm.
B is BMI
kk.k is the BMI
U is units (lb or kg; in or cm)
uu is LB or KG
E is end of packet.

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 19 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
TROUBLESHOOTING
SYMPTOM
REASON/CORRECTIVE ACTION
The characters only appear on half of the
display.
Ensure AC power supply is firmly plugged in
Press the “WEIGH” button or remove one battery.
Wait five seconds, then re-install the battery and try
the “WEIGH” button again.
The display lights appear to work, but do
not respond to button activation.
Check to ensure the membrane switch label is correctly
plugged into display board.
Check to ensure the calibration switch is not in the
Calibration Mode (Figure 10).
The display shows no reading at all.
Ensure AC power supply is firmly plugged in
Check to ensure batteries are installed correctly (see
directions for BATTERY REPLACEMENT).
Check display cable to make sure it is connected
securely.
For additional information or assistance, telephone our Service Hotline: [phone]
or e-mail: [e-mail]

Model SR555iStand-On Scale
Operating and Service Manual
Part No. MAN555i_MICROBAN_201001 Page 20 of 22
SInstruments, Inc., 600 Young Street, Tonawanda, NY 14150
Tel: [phone] Fax: [phone] URL: www.srscales.com
email: [email protected]m Copyright 2020 SInstruments, Inc.
WARRANTY
FOUR YEAR LIMITED WARRANTY
Each S system is manufactured with high quality components. SR Instruments, Inc.
warrants that all new equipment will be free from defects in material or workmanship, under
normal use and service, for a period of four (4) years from the date of purchase by the original
purchaser. Normal wear and tear, injury by natural forces, user neglect, and purposeful
destruction are not covered by this warranty. Warranty service must be performed by the factory
or an authorized repair station. Service provided on equipment returned to the factory or
authorized repair station includes labor to replace defective parts. Goods returned must be shipped
with transportation and/or broker charges prepaid. SR Instruments, Inc.’s obligation is limited to
replacement of parts that have been so returned and are disclosed to SR Instruments, Inc.’s
satisfaction to be defective. The provisions of this warranty clause are in lieu of all other
warranties, expressed or implied, and of all other obligations or liabilities on SR Instruments,
Inc.’s part, and it neither assumes nor authorizes any other person to assume for SR Instruments,
Inc. any other liabilities in connection with the sale of said articles. In no event shall SR
Instruments, Inc. be liable for any subsequent or special damages. Any misuse, improper
installation, or tampering, shall void this warranty.
DAMAGED SHIPMENTS
Title passes to purchaser upon delivery to Transportation Company. Purchaser should file any
claims for shortage or damage with the delivery carrier and should refuse any shipment that has
obvious external damage.
RETURN POLICY
All products being returned to SR Instruments, Inc. require a Return Goods Authorization number
(RGA). To receive an RGA, call our Customer Service at 716-693-5977 ext 103 or toll-free in the
USA and Canada at 800-654-6360 ext 103.
When inquiry is made, please supply model and serial numbers, purchase order and reason for
return.
Generally, deleted, damaged, and outdated merchandise will not be accepted for credit. A
minimum restocking charge of 15% will be assessed on return of current merchandise unless scale
is returned because of SR error.
No returns will be accepted after 30 days.
All returns are to be shipped FREIGHT PREPAID to: SR Instruments, Inc., 600 Young Street,
Tonawanda, NY 14150.
RESTOCKING FEE
15% fee will be assessed on return of current merchandise
No fees will be charged if the scale is returned because of an error on the part of SR
Instruments, Inc.
No returns accepted after 30 days.