APG MPX-E User manual

APG
R
Doc #9003761
Part #200204
Rev G, 06/2022
MPX Magnetostrictive Level Sensors
User Manual
For The MPX-E, MPX-E Chemical, and MPX-R

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Table of Contents
Introduction ................................................................................................................ iii
Warranty and Warranty Restrictions.................................................................... iv
Chapter 1: Specications and Options..................................................................... 1
Dimensions ....................................................................................................................................1-3
Specications ................................................................................................................................... 4
Model Number Congurator.......................................................................................................5-7
Electrical Connections and System Wiring Diagrams ........................................................ 8-9
Chapter 2: Installation and Removal Procedures and Notes............................10
Tools Needed................................................................................................................................... 10
Physical Installation Notes ......................................................................................................... 10
Physical Installation Instructions ..............................................................................................11
Electrical Installation ....................................................................................................................11
Removal Instructions ................................................................................................................... 12
Chapter 3: Programming ..........................................................................................12
Modbus Programming .................................................................................................................. 12
Modbus Programming with RST-6001 and APG Modbus Software .................................... 12
4-20 mA Programming with RST-4100 and APG Modbus Software.................................... 13
Modbus Register Lists For MPX-E/R4 ..................................................................................13-14
MPX-E/R4 Modbus Sensor Parameters................................................................................ 15-19
APG Modbus Register Lists for MPX-E/R2 and MPX-E/R3 ............................................. 19-20
MPX-E/R2 and MPX-E/R3 APG Modbus Sensor Parameters...........................................21-25
MPX-E/R Application Type Parameters..............................................................................26-30
Chapter 4: Maintenance ........................................................................................... 31
General Care.................................................................................................................................... 31
Repair and Returns........................................................................................................................ 31
Chapter 5: Hazardous Location Installation and Certication.........................32
Hazardous Location and Non-Incendive Wiring Diagram....................................................32
CSA Certicate of Compliance.............................................................................................. 33-35

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Introduction
Thank you for purchasing an MPX series magnetostrictive level sensor from APG. We appreciate your
business and your trust. Please take a few minutes to familiarize yourself with your MPX and this manual.
The MPX level sensor provides highly accurate and repeatable level readings in a wide variety of liquid level
measurement applications. It is certied for installation in hazardous areas in the US and Canada by CSA
for Class I, Division 1 & 2 and Class I, Zones 1 & 2 environments. The MPX-R’s large, buoyant, and robust
oats allow it to be used in harsh applications where fouling or buildup might otherwise be of concern.
The smaller, lighter weight oats of the MPX-E allow it to be used in applications where space is limited.
The MPX-E Chemical has a chemical resistant coating, allowing for use in corrosive, acidic, and marine
environments.
Reading your label
Every APG instrument comes with a label that includes the instrument’s model number, part number,
and serial number. Please ensure that the part number on your label matches your order. The following
electrical ratings and approvals are also listed on the label. Please refer to the Certicate of Compliance at
the back of this manual for further details.
Electrical ratings
Rated 12 - 24 VDC, 4-20 mA, or 80 mA
Class I, Division 1 & 2, Groups C, and D T4 (Ta 85°C)
Ex d IIB T4 (Ta 85°C)
Ex nA IIB T4 (Ta 85°C)
Class I, Zone 1; AEx d IIB T4 (Ta 85°C)
Class I, Zone 2; AEx na IIB T4 (Ta 85°C)
Non-Incendive Wiring Requirements: Vmax Ui= 28VDC, Imax Ii = 200ma, Ci = 0nF, Li = 0μH
IMPORTANT: MPX level sensor MUST be installed according to drawing 9003468 on
page 32 to meet listed approvals. For Class I, Division 1 and Class I, Zone 1 approvals,
seal required within 18 inches of the enclosure. Faulty installation will invalidate all safety
approvals and ratings.
DANGER: WARNING -- EXPLOSION HAZARD -- SUBSTITUTION OF COMPONENTS MAY IMPAIR SUITABILITY
FOR CLASS I, DIVISION 2;
AVERTISSEMENT -- RISQUE D’EXPLOSION -- LA SUBSTITIOND E COMPOSANTSP EUTR ENDRE CE MATERIEL
INACCEPTABLE POUR LES EMPLACEMENTS DE CLASSE I, DIVISION 2.
DANGER: WARNING -- EXPLOSION HAZARD -- DO NOT DISCONNECT EQUIPMENT UNLESS POWER HAS
BEEN SWITCHED OFF OR THE AREA IS KNOWN TO BE NON-HAZARDOUS;
AVERTISSEMENT -- RISQUE D’EXPLOSION -- AVANT DE DECONNECTER L’EQUIPEMENT, COUPER LE COURANT
OU S’ASSURER QUE L’EMPLACEMENT EST DESIGNE NON DANGEREUX.
DANGER: OPEN CIRCUIT BEFORE REMOVING COVER or KEEP COVER TIGHT WHILE CIRCUITS ARE ALIVE;
AVERTISSEMENT -- OUVRIR LE CIRCUIT AVANT D’ENLEVER LE COUVERCLE, or GARDER LE COUVERCLE BIEN
FERME TANT QUE LES CIRCUITS SONT SOUS TENSION.
US
C
237484
DANGER: WARNING -- POTENTIAL ELECTROSTATIC CHARGING HAZARD - CLEAN ONLY WITH A DAMP
CLOTH;
AVERTISSEMENT -- DANGER DE CHARGE ELECTROSTATIQUE POTENTIEL - NETTOYER SEULEMENT AVEC UN
CHIFFON HUMIDE.

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Warranty and Warranty Restrictions
This product is covered by APG’s warranty to be free from defects in material and workmanship under
normal use and service of the product for 24 months. For a full explanation of our Warranty, please visit
https://www.apgsensors.com/about-us/terms-conditions. Contact Technical Support to receive a Return
Material Authorization before shipping your product back.
Scan the QR code below to read the full explanation of our Warranty on your tablet or smartphone.

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Chapter 1: Specications and Options
MPX-E Sensor and Float Dimensions
• Dimensions
1.91”
1.88”
G
Float Ref.
S1=6”
S2=2.38”
Float Options
2.00”
2.06”
A & B
Float Ref.
S1=6”
S2=1.4”
1.38”
1.63”
C & D
2.20”
1.47”
F
1.87”
1.78”
E
Float Ref.
S1=6”
S2=1.1”
Float Ref.
S1=6”
S2=2.27”
Float Ref.
S1=6”
S2=1.5”
S2
Dead-Band
(from Float
Ref. to bottom
of stem)
Min. 12”
Max. 153”
S1
Dead-Band
(from Zero
Reference to
Float Ref.)
3/4” NPT
1/2” NPT
2.38”
4.94”
4.15”
ZERO
REFERENCE
GROUND
SCREW
7.32-7.44”
6.53-6.65”
Note:
For dual dimensions, large
housing dimensions are
above small housing
dimensions.
5.00”
4.25”
5.71”
4.92”
3/4” NPT
1/2” NPT
Housing
Connection
Location
Ø 0.27”
4.21”
3.74”

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MPX-E Chemical Sensor and Float Dimensions
4.21”
3.74”
7.07”
6.28”
5.00”
4.25”
5.71”
4.92”
Kynar Float
S1
Dead-Band
(from Zero
Reference to
Float Ref.)
S2
Dead-Band
(from Float
Ref. to bottom
of stem)
3/4” NPT
1/2” NPT
2.13”
4.94”
4.15”
ZERO
REFERENCE
Min. 12”
Max. 153”
1.91”
1.88”
G
Float Ref.
S1=6”
S2=2.38”
Note:
S2 increases to 2.88” if bottom float stop used.
GROUND
SCREW
3/4” NPT
1/2” NPT
Housing
Connection
Location
Note:
For dual dimensions, large
housing dimensions are
above small housing
dimensions.
Ø 0.27”

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MPX-R Sensor and Float Dimensions
5.00”
5.71”
5.00”
5.10”
5.88”4.98”
3.03”
3.00”
5.50”
3.08”
2.80”
3.07”
Float Ref.
S1=10.63”
S2=6”
Float Ref.
S1=12.25”
S2=4.25”
Float Ref.
S1=12.25”
S2=4.25”
Float Options
Y & Z / L & M
W & X
S & T
U & V / I & J
I & J U & V
4.21”
6.84” - 6.97”
S1
Dead-Band
(from Zero
Reference to
Float Ref.)
S2
Dead-Band
(from Float
Ref. to bottom
of stem)
Float
Ref.
S1=10”
S2=6.5”
3/4” NPT
1.90”
4.94”
2.00”
Y & Z
L & M
U & V
I & J
Min. 48”
Max. 300”
ZERO
REFERENCE
GROUND
SCREW
Ø 0.27”
3/4” NPT
Housing
Connection
Location

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Performance
Resolution 4-20 mA: 14 bit DAC (1 mm)
Modbus: 0.04 in. (1 mm)
Accuracy Greater of ±0.05% of FS or 1 mm
RTD - 1k Ohm Accuracy: ±1°C
Environmental
Probe Operating Temperature -40° to 85° C (-40° to 185° F)
Storage Temperature -45° to 90° C (-49° to 194° F)
Enclosure Protection IP65
Maximum Operating Pressure MPX-E Chem Float: 30 PSIA @ 21° C (70° F)
Electrical
Supply Voltage 12-24 VDC at sensor
Current Draw Modbus (RS-485): 25 mA (typical, MPX-E)
28 mA (typical, MPX-R)
4-20 mA: 4-22 mA single / 8-44 mA dual (typical)
Protection Reverse Polarity
Surge (Output 4)
Materials of Construction
Housing Cast aluminum, epoxy coated
Stem MPX-E: 0.5” Ø 316L SS
MPX-E Chemical: 0.5” Ø 316L SS with chemical
resistant coating
MPX-R: 1” Ø 316L SS
Mounting 316L SS
Compression Fitting (slide) Aluminum with Neoprene bushing
Connectivity
Output Modbus RTU (RS-485), optional temperature
2 wire, loop-powered 4-20 mA
3 wire, loop-powered dual 4-20 mA
4-20 mA Set points
4 mA MPX-E, E Chem: Bottom of probe
MPX-R: Bottom of probe
20 mA MPX-E, E Chem: 6 inches below probe zero point
MPX-R: 10 inches below probe zero point
Programming
RS-485 Optional RST-6001 USB-to-RS-485 converter
4-20 mA Optional RST-4100 programming module
• Specications

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• Model Number Congurator
Model Number: MPX - _E_ _____ _____ - _____ _____ - _____ _____ _____ __B__ - _____ - _____
A B C D E F G H I J K
A. Stem Type
□E 0.5 in. diameter 316L SS
B. Output
□2 Single oat, 4-20 mA (loop powered, 2 wire)
□3 Dual oat, 4-20 mA (loop powered, 3 wire)
□4 Modbus RTU, surge protection
C. Housing Type
All Housing Die-cast Aluminum, IP65, Blue
□__▲ Large Housing
□A Small Housing†
D. Float 1 (Top Float)
□A 316L SS Round (0.65 SG)
□B 316L SS Round (0.92 SG)
□C 316L SS Cylindrical (0.65 SG)
□D 316L SS Cylindrical (0.92 SG)
□E Buna-N (0.5 SG)
□F 316 SS 3A Cylindrical (0.5 SG)
□G Kynar Cylindrical (0.66 SG)
E. Float 2 (optional)
□N None
□B 316L SS Round (0.92 SG)††
F. Mounting Type
□P▲ NPT Plug 150#
□NNone
▲Note: This option is standard
†Note: Small housing only available with Modbus RTU (Output 4)
††Note: Float 2 option B requires Float 1 option A
G. Mounting Size
□1.5 1.5 in. (welded or slide connection)
□2▲ 2 in. (welded or slide connection)
□3 3 in. (slide connection only)
□NNone
H. Mounting Connection
□W Welded (xed)
□S Slide with Compression Fitting (adjustable)
I. Stem/Finish Material
□B 316L SS
J. Total Stem Length in Inches
□__ Min. 12 in. - Max. 153 in.
K. Optional Temperature Sensor
MPX-E4
□N▲None
□T Stem RTD, 1kΩ, 6 in. from bottom of probe

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Model Number: MPX - _E_ _____ _____ - __G__ __N__ - __P__ __2__ __W__ __E__ - _____ - _____
A B C D E F G H I J K
A. Stem Type
□E 0.5 in. diameter 316L SS
B. Output
□2 Single oat, 4-20 mA (loop powered, 2 wire)
□4 Modbus RTU, surge protection
C. Housing Type
All Housing Die-cast Aluminum, IP65, Blue
□__▲ Large Housing
□A Small Housing†
D. Float 1
□G Kynar Cylindrical (0.66 SG)
E. Float 2
□N None
F. Mounting Type
□P NPT Plug 150#
G. Mounting Size
□2 Size 2
▲Note: This option is standard
†Note: Small housing only available with Modbus RTU (Output 4)
H. Mounting Connection
□W Welded (xed)
I. Stem/Finish Material
□E Chemical resistant ETFE (Fluon®) coating
J. Total Stem Length in Inches
□__ Min. 12 in. - Max. 153 in.
K. Optional Temperature Sensor
MPX-E4
□N▲None
□T Stem RTD, 1kΩ, 6 in. from bottom of probe

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Model Number: MPX - _R_ _____ _____ - _____ _____ - _____ _____ _____ _B_ - _____ - _____
A B C D E F G H I J K
A. Stem Type
□R 1 in. diameter 316L SS
B. Output
□2 Single oat, 4-20 mA (loop powered, 2 wire)
□3 Dual oat, 4-20 mA (loop powered, 3 wire)
□4 Modbus RTU, surge protection
C. Housing Type
All Housing Die-cast Aluminum, IP65, Blue
□__ Large Housing
D. Float 1 (Top Float)
□Z/Y 5.5h x 3d in. Red Polyurethane (0.65/0.94 SG)
□X/W 5 in. Round 316L SS (0.52/0.92 SG)
□V/U 6h x 3d in. Oval 316L SS (0.58/0.94 SG)
□T/S 3 in. Round 316L SS (0.60/0.94 SG)
□M/L 5.5h x 2d in. Red Polyurethane (0.57/0.94 SG)
□J/I 5h x 3d in. Oval Titanium (0.60/0.94 SG)
□N None
E. Float 2 (optional)
□N None
□Y 5.5h x 3d in. Blue Polyurethane (0.94 SG)
□W 5 in. Round 316L SS (0.92 SG)
□U 6h x 3d in. Oval 316L SS (0.94 SG)
□S 3 in. Round 316L SS (0.94 SG)
□L 5.5h x 2d in. Blue Polyurethane (0.94 SG)
□I 5h x 3d in. Oval Titanium (0.94 SG)
F. Mounting Type
□P▲ NPT Plug 150#
□N None
▲Note: This option is standard
G. Mounting Size
□2▲ 2 in. (welded or slide connection)
□3 3 in. (slide connection only)
□NNone
H. Mounting Connection
□W Welded (xed)
□S Slide with Compression Fitting (adjustable)
I. Stem/Finish Material
□B 316L SS
J. Total Stem Length in Inches
□__ Min. 48 in. - Max. 378 in.
K. Optional Temperature Sensor(s)
MPX-R4
□NNone
□T▲ Stem RTD, 1kΩ, 6 in. from bottom of probe

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• Electrical Connections and System Wiring Diagrams
IMPORTANT: Refer to Chapter 5 for Hazardous Location and Non-Incendive Wiring
diagram.
Modbus System Wiring
Modbus System Wiring with RST-6001
Power
Supply
+12-24 Vdc
GND Use Shielded Cable
120 Ω
terminating
resistor
120 Ω
terminating
resistor at
last sensor
V+
B
A
Sensor 1
GND
V+
B
A
Sensor 2
GND
V+
B
A
Sensor 3
GND
Server
Device
RS-485 A
RS-485 B
MPX Modbus
series sensor
MPX Modbus
series sensor
MPX Modbus
series sensor
EARTH
GND
Note: Earth Ground terminal is factory
connected to internal housing ground
lug. EARTH
GND
EARTH
GND
Power
Supply
+12-24 Vdc
GND Use Shielded Cable
Equivalent 120 Ω
terminating resistor
internal to RST-6001
120 Ω
terminating
resistor at
last sensor
USB to computer
with APG Modbus
software
RST-6001
Modbus
Controller
V+
B
A
Sensor 1
GND
V+
B
A
Sensor 2
GND
V+
B
A
Sensor 3
GND
A
B
-5V
MPX Modbus
series sensor
+5V
MPX Modbus
series sensor
MPX Modbus
series sensor
Note: An independent +12-24 Vdc
power supply is required when
using an RST-6001 Modbus Controller.
The RST-6001 can only supply ±5 Vdc,
not the +12-24 Vdc required by the MPX.
EARTH
GND
EARTH
GND
EARTH
GND
Note: Earth Ground terminal is factory
connected to internal housing ground lug.
IMPORTANT: For surge protection on MPX-E4 or -R4, either connect the grounding
screw (see pages 1-3) to an earth ground, or ensure that the tank mounting of the MPX is
grounded.

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4-20 mA Loop Wiring
12-24 Vdc
Out (1)
Power
Source
(14- 24 Vdc)
Sensor
Out 24V
RST-4100
Load Resistor
(150 Ω to 700 Ω)
Wired in series for
programming.
+
−
Note: a minimum of
14 Vdc is required to
establish communications
with the RST-4100
Programming Module
and APG Modbus software
required for programming
MPX-E2, -R2 and MPX-E3,
-R3 series sensors.
USB to computer
with APG Modbus
software
Out 2
MPX-E2, -R2 or
MPX-E3, -R3 series
sensor.
Programming configuration is
for programming ONLY. After
programming, sensor must be
reintegrated to 4-20 mA loop
for proper system operation.
12-24 Vdc
Out 1
Out 2
Input 1 Input 2 Com
Receiver
Sensor
Sensor
4-20 mA Dual Float Loop Wiring
(MPX-E3 and MPX-R3 Series)
Input Com
Receiver 1
Input Com
Receiver 2
OR
+
Power Source
(12-24 Vdc)
−
12-24 Vdc
Out 1
Out 2
Sensor
+
Power Source
(12-24 Vdc)
−
12-24 Vdc
Out
4-20 mA Single Float Loop Wiring
(MPX-E2 and MPX-R2 Series)
Input Com
Receiver
+
Power Source
(12-24 Vdc)
−
4-20 mA Programming Wiring
NOTE: For MPX-E3 & MPX-R3 se-
ries sensors, - Vdc from power source
must be connected to Output1 on
sensor for correct sensor program-
ming.
IMPORTANT: Refer to Chapter 5
for Hazardous Location and Non-In-
cendive Wiring diagram.

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Chapter 2: Installation and Removal Procedures and Notes
You will need the following tools to install your MPX level sensor:
• Wrench sized appropriately for MPX mounting
• Wrench sized appropriately for conduit connections
• Flat-head screwdriver for wire terminals
• Channellock pliers for tightening compression tting
• 3/32” hex Allen wrench for 1-piece MPX-E oat stops
• 1/8” hex Allen wrench for 1-piece MPX-R oat stops
• 3/16” hex Allen wrench for 2-piece MPX-R oat stops
• Tools Needed
The MPX should be installed in an area--indoors or outdoors--which meets the following conditions:
• Ambient temperature between -40°C and 85°C (-40°F to +185°F)
• Relative humidity up to 100%
• Altitude up to 2000 meters (6560 feet)
• IEC-664-1 Conductive Pollution Degree 1 or 2
• IEC 61010-1 Measurement Category II
• No chemicals corrosive to stainless steel (such as NH3, SO2, Cl2 etc.)
• Ample space for maintenance and inspection
Additional care must be taken to ensure:
• The probe is located away from strong magnetic elds, such as those produced by motors, transform-
ers, solenoid valves, etc.
• The medium is free from metallic substances and other foreign matter.
• The probe is not exposed to excessive vibration.
• The oat(s) t through the mounting hole. If the oat(s) does/do not t, it/they must be mounted on
the stem from inside the vessel being monitored.
• The oat(s) is/are oriented properly on the stem (See Figure 2.1). MPX-E oats will be installed by the
factory. MPX-R oats are typically installed by customer.
• Physical Installation Notes
DANGER: WARNING -- POTENTIAL ELECTROSTATIC CHARGING HAZARD - CLEAN ONLY WITH A DAMP
CLOTH;
AVERTISSEMENT -- DANGER DE CHARGE ELECTROSTATIQUE POTENTIEL - NETTOYER SEULEMENT AVEC UN
CHIFFON HUMIDE.
IMPORTANT: MPX level sensor MUST be installed according to drawing 9003468 on
page 32 to meet listed approvals. For Class I, Division 1 and Class I, Zone 1 approvals,
seal required within 18 inches of the enclosure. Faulty installation will invalidate all safety
approvals and ratings.

11
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Figure 2.1
UP
Taper IMPORTANT: Floats must be oriented properly
on the stem, or sensor readings will be inaccurate
and unreliable. Untapered oats will have a sticker
or “N” indicating the top of the oat. Remove sticker
prior to use.
• Remove the housing cover of your MPX.
• Feed system wires into MPX through 3/4” NPT conduit openings. Fittings must be UL/CSA Listed for CSA
installation and IP65 Rated or better.
• Connect wires to MPX terminals. Use crimped ferrules on wires, if possible.
• Replace the housing cover.
• For surge protection on MPX-E4 and MPX-R4 models, either connect the grounding screw (see
dimensions on page 1-3) to an earth ground, or ensure that tank mounting of MPX is grounded.
See Electrical Connections and System Wiring Diagrams (pages 8-9) for Modbus and 4-20 mA wiring
examples.
• Electrical Installation
• If your sensor’s stem and oats t through the mounting hole, carefully lower the assembly into the
vessel, then secure the sensor to the vessel.
• If the oats do not t, mount them on the stem from inside the vessel being monitored. Then secure
the sensor to the vessel.
• For sensors with oat stops, refer to the assembly drawing included with the sensor for oat stop
installation locations.
• For MPX-E Chemical, ensure probe is concentric with tting so as not to scrape chemical resistant coat-
ing o against threads of tting.
• Physical Installation Instructions
IMPORTANT: WARNING -- A SEAL SHALL BE INSTALLED WITHIN 18 inches OF THE ENCLOSURE;
AVERTISSEMENT -- UN SCELLEMENT DOIT ETRE INSTALLÉ A MOINS DE 18 inches DU BOITIER.

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Removing your MPX level sensor from service should be done with care.
• If the oats on your sensor t through the mounting hole, carefully lift the entire sensor assembly out
of and away from the vessel.
• If the oats on your sensor do not t through the mounting hole, they will need to be removed from
the stem before the sensor can be removed. Be sure to drain the vessel being monitored to allow ac-
cess to the oats and stem for removal.
• Clean the stem and oats of any build up or debris and inspect for damage.
• Store your sensor in a dry place, at a temperature between -45° and 90° C (-49° and 194° F).
• Removal Instructions
MPX-E4 and MPX-R4 series sensors use standard Modbus RTU protocol (RS-485). The sensors can only oper-
ate as client devices. Sensor default transmission settings are 9600 Baud, 8 Bits, 1 Stop Bit, No Parity, and
require a minimum delay of 300 ms between transactions. See MPX-E/R4 Modbus Register Lists on pages 13
and 14.
Chapter 3: Programming
• Modbus Programming
NOTE: For more information about Modbus RTU, please visit www.modbus.org.
NOTE: MPX-E1 and MPX-R1 legacy models have the same Modbus settings and regis-
ters as MPX-E4 and MPX-R4.
An APG RST-6001 Modbus Controller can be used in tandem with APG Modbus to program and control up
to 20 MPX-E/R1 (legacy models) or MPX-E/R4 series sensors. Through APG Modbus, you can monitor the raw
readings from the sensor, congure the data for distance, level, volume, or weight, and enter measurements
for a strapping chart. See MPX-E/R4 Modbus Register Lists on pages 13 and 14.
• Modbus Programming with RST-6001 and APG Modbus Software
NOTE: For APG Modbus programming instructions, or to download APG Modbus soft-
ware, please visit www.apgsensors.com/suppport.

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An APG RST-4100 Programming Module can be used in tandem with APG Modbus to program a single
MPX-E2/3 or MPX-R2/3 series sensor. Through APG Modbus, you can congure the 4 mA and 20 mA output
setpoints and calibration settings. If your monitoring equipment (PLC, etc.) can be congured to interpret
the 4-20 mA output(s) of the MPX as volume, then the MPX can be congured accordingly via APG Modbus.
See MPX-E/R2 & MPX-E/R3 Modbus Register Lists on pages 19 and 20.
However, the RST-4100 is not designed to be used for continuous monitoring of a sensor. After
programming your MPX sensor, the RST-4100 must be removed and the wiring returned to normal. See 4-20
mA Loop Wiring and 4-20 mA Programming Wiring on page 9.
• 4-20 mA Programming with RST-4100 and APG Modbus Software
• Modbus Register Lists for MPX-E/R4
Input Registers (0x04)
Register Returned Data
30299 Model Type
30300 Top Distance (raw oat reading, in mm, unsigned)
30301 Bottom Distance (raw oat reading, in mm, unsigned)
30302 Temperature Reading (in 0C, signed)
30303-30304 Top Calculated (level, volume, etc., in selected Units)
30305-30306 Bottom Calculated (level, volume, etc., in selected Units)
30307 Version
NOTE: The Calculated Readings will be returned without a decimal place. In order to
obtain the true result, the Decimal Place setting must be taken into account.
NOTE: Input Registers 30300 and 30301 also display Loss of Signal error codes. See
Application Type (Holding Register 40402).

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Holding Registers (0x03)
Register Function Value Range
40400 Device Address 1 to 247
40401 Units 1, 2, 3
40402 Application Type 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11
40403 Volume Units 1, 2, 3, 4, 5, 6, 7
40404 Decimal Place 0, 1, 2, 3
40405 †Max Distance 0 to 11,278 mm
40406 Full Distance 0 to 10,364 mm
40407 Empty Distance 0 to 11,278 mm
40408 †Sensitivity 0 to 100
40409 †Pulses 0 to 20
40410 † Blanking 0 to 10,364 mm
40411 NA NA
40412 Averaging 1 to 31
40413 Filter Window 0 to 10,364 mm
40414 Out of Range Samples 1 to 255
40415 Sample Rate 10 to 1,000 msec.
40416 † Multiplier 1 to 1,999 (1000 = 1.000)
40417 † Oset -10,364 to 10,364 mm
40418 †Pre lter 0 to 10,364 mm
40419 †Noise limit 0 to 255
40420 Temperature Select 0 to 8
40421 RTD Oset (0C) -100 to 100
40422 †Float Window 0 to 1,000 mm 0=1 oat
40423 1st Float Oset -10,364 to 10,364
40424 2nd Float Oset -10,364 to 10,364
40425 †Gain Oset 0 to 255
40426 4 mA Set Point NA*
40427 20 mA Set Point NA*
40428 4 mA Calibration NA*
40429 20 mA Calibration NA*
40430 t1d NA*
40431 t1w NA*
40432 t1t NA*
40433 t2d NA*
40434 t2w NA*
40435 t2t NA*
40436-40437 Parameter 1 Data 0 to 1,000,000 mm
40438-40439 Parameter 2 Data 0 to 1,000,000 mm
40440-40441 Parameter 3 Data 0 to 1,000,000 mm
40442-40443 Parameter 4 Data 0 to 1,000,000 mm
40444-40445 Parameter 5 Data 0 to 1,000,000 mm
*These registers are not used by the MPX-E4 or -R4, even though they are labeled in the APG Modbus
software.
†Setting is factory calibrated. Do not adjust.

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Determines the type of Calculated Reading (Input Register 30303-04 and 30305-06) performed by the sensor
and associated Loss of Signal Error Code.
0 = Distance
1 = Level
2 = Standing Cylindrical Tank with or without Hemispherical Bottom
3 = Standing Cylindrical Tank with or without Conical Bottom
4 = Standing Rectangular Tank with or without Chute Bottom
5 = Horizontal Cylindrical Tank with or without Spherical Ends
6 = Spherical Tank
7 = Pounds (Linear Scaling)
8 = N/A
9 = Vertical Oval Tank
10 = Horizontal Oval Tank
11 = Strapping Chart
See MPX-E/R Application Type Parameters pages 26-30.
For Output 4, Loss of Signal Error Codes are dependent on Application Type. Loss of Signal for Application
Type 0 (Distance) is Max Distance (Holding Register 40405). For all other Application Types, Loss of Signal is
0.
• MPX-E/R4 Modbus Sensor Parameters
40401 - Units
Determines the units of measure for the calculated reading when Application Type is set to 0, 1, or 7.
1 = Feet 2 = Inches 3 = Meters
40402 - Application Type
40403 - Volume Units
Determines the units of measure for the calculated reading when Application Type is set to 2 - 6 or 9 -11.
1 = Feet3 5 = Liters
2 = Million Feet3 6 = Inches3
3 = Gallons 7 = Barrels
4 = Meters3

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40404 - Decimal Place
Determines the number of decimal places included in the Calculated Reading(s). The Calculated Reading will
always be returned as a whole number.
For example, a Calculated Reading of 1126.658 (gallons, ft3, etc.) will be returned as follows:
Decimal Place = 0 Volume = 1127 (rounded to nearest whole number)
Decimal Place = 1 Volume = 11267 (divide by 10 to get true result)
Decimal Place = 2 Volume = 112666 (divide by 100 to get true result)
Decimal Place = 3 Volume = 1126658 (divide by 1000 to get true result)
40405 - Maximum Distance (Factory Calibrated)
Sets the distance (beginning from the Zero Reference) to the point where the sensor will stop looking for oat
signals, usually the bottom of the stem. A oat beyond the Maximum Distance value will not be detected.
40406 - Full Distance
Sets the positive distance (beginning from the sensor Zero Reference) to the point where the monitored
vessel is considered full.
40407 - Empty Distance
Sets the positive distance (beginning from the Zero Reference) to the point where the monitored vessel is
considered empty (usually the bottom of the stem).
40408 - Sensitivity (Factory Calibrated)
Sets the level of gain that is applied to the returning oat signal.
40409 - Pulses (Factory Calibrated)
Controls the duration of the signal being sent down the magnetostrictive wire.
40410 - Blanking (Factory Calibrated)
Sets the blanking distance, which is the zone from the Zero Reference of the sensor to the point from which
the rst signal will be valid. Signals from a oat in the blanking area will be ignored.