Precision Digital PD6730X NEMA 4X Modbus Scanner

• Modbus Master, Slave, or Snooper Mode
• Scan up to 16 Modbus Process Variables
• 5-Digit Decimal or Feet & Inches Level Display
• On-Board Three-Wire RS-485 with Modbus
• Independent Scaling, Tag, and Unit for Each PV
• 7 Alphanumeric Character 0.4″ (10.2 mm) Lower Display for Process Variables, Custom Units, and Tags
• Injection-Molded, IP65, NEMA 4X Enclosure
• SafeTouch Through-Window Button Programming
• Isolated 4-20 mA Output Option
• Pulse Input for Rate, Total, and Grand Total
• 13-Digit Totalizer with Total Overflow Feature
• Password Protection
• Backlight Standard on All models
• Automatic Rate, Total, and Grand Total Unit Conversions
• Operates from -40 to 75°C
• Data Logging Functions and Modbus Accessible Data
• Two Isolated Pulse Outputs Standard, Up to 5 kHz

General

Decimal Display: Top Display: Five Digits (0 to 99999), 0.7″ (17.8 mm) high, 7-segment, automatic lead zero blanking. 
Bottom Display: Seven Characters, 0.4″ (10.2 mm) high, 14-segment, automatic lead zero blanking.
Symbols: Total, grand total, high alarm, low alarm, SafeTouch button sleep mode/disable, password lock.
Feet & Inches Display: Top Display: 0.60″ (15.2 mm) high, 0 to 399FT, 11 and 15/16 IN, 7-segment, programmable 1/16 or 1/8 fraction display.
Bottom Display: Seven Characters, 0.4″ (10.2 mm) high, 14-segment, 7-digits.
Tank Level Indicator: 20-segments, F (Full) and E (Empty).
Alarm Indication: High and low alarm
Backlight: White
Display Assignment: Top and Bottom Display*: Process Variables (PV); Alternating PV and Units, Tag and PV, or Tag, PV, and Units; Pulse Input Rate, Total, or Grand Total with Alternating Tag.
Bottom Display: All Top Display Options or Off
Units and tag independent for each PV, pulse input rate, total, and grand total.
*Note: On feet and inches display Models, top display used only for level Modbus process variables or math channels.
Backlight: White LED, 10 sec auto-off when battery powered. Backlight deactivated below temperature ≈ -20°C
Alarm Indication: Flashing display plus HI/LO (alarm) or SET indicators. 
Scan and Update Rate: Ambient > -20°C: Modbus PV scan rate programmable from 2 to 99 seconds per PV. Tag and units programmable for 1 to 5 second alternation. Pulse input variables update 1/second. Rate update is dependent on gate settings.
Ambient < -20°C: All Modbus scan, alternating units and tags, and pulse input variables update/10 seconds minimum.
Underrange: Upper Display: Decimal display flashes -9999
Level display flashes to 399FT, 11 and 15/16 IN
Lower Display: Flashes -999999
Overrange: Upper Display: Decimal display flashes 99999
Level display flashes to 399FT, 11 and 15/16 IN
Lower Display: Flashes 9999999
Programming Method: Four SafeTouch through-window buttons when cover is installed. Four internal push buttons when cover is removed.
Recalibration: Calibrated at the factory to read frequency in Hz. No recalibration required. .
Password Menu Options: Three programmable password selections can be used for the following: restrict modification of settings, prevent resetting the total or grand total without the password, or permanently lock out the ability to change or reset the grand total or any grand total related settings(making a non-resettable grand total).
  Pass: Restricts modifications of programmed settings to require re-entering the password to make changes.
  Pass T: Restricts the reset of total to require re-entering the password. Disables the manual mode reset contact.
  Pass GT: Restricts the reset of grand total to require re-entering the password. May enable a non-resettable grand total and permanent lockout of grand total-related settings with a specific password.
Input Power: 9-30 VDC, 38 mA max. 2.2 W
Data Logging: Up to 512 records, recorded 4/day at specific times or at defined time intervals. Record contains first eight enabled Modbus PVs; C1-4 if enabled; date; time; pulse rate, total, and grand total with units; and log number.
Isolation: All models: 500 V opto-isolated pulse input-to-power/OC output with isolated input enabled, 500 V input/power-to-RS-485 serial communications. AXA models: 500 V input/power-to-analog output.
Environmental: Operating temperature range: -40 to 75°C; Storage temperature range: -40 to 75°C; Backlight deactivated below temperatures ≈ -20°C; Relative humidity: 0 to 90% non-condensing 
Non-Volatile Memory: All programmed settings and total reading are stored in non-volatile memory for a minimum of ten years if power is lost. 
Connections: Screw terminals accept 12 to 22 AWG wire
Enclosure: NEMA 4X, IP65 plastic field enclosure. Color: grey. Material: Polycarbonate with UV Stabilizer. Three ¾” NPT threaded conduit openings. Two ¾” NPT plastic conduit plugs, with 1.29″ wrenching flats and a screwdriver slot, are included.
Mounting: May be mounted directly to conduit. Two slotted flanges for wall mounting or NPS 1½” to 2½” or DN 40 to 65 mm pipe mounting.
Display Orientation: Display may be mounted at 90° increments up to 270° from default orientation.
Overall Dimensions: 5.67″ x 5.25″ x 4.18″ (144 mm x 133 mm x 106 mm) (W x H x D)
Weight: 1.65 lbs (26.4 oz, .75 kg)
Warranty: 3 years parts and labor

Modbus Operating Modes

Master: Processes and displays data read from Modbus RTU slave devices. Up to 16 process variables (PVs) from up to 16 slave devices. Each PV programmed individually.
Slave: Processes data sent to it from a Modbus RTU master device.
Snooper: Listens to the Modbus traffic and picks up a specific register or registers being polled by a Master device from a specific slave device and processes the data being read. Up to 16 process variables (PVs) from up to 16 devices. If multiple registers are polled by the master with one command, only the first returned value will be read.
Master Poll Time: 0.1 to 99.9 sec. Time between read-commands.
Master Timeout: 0.1 to 99.9 seconds. Time elapsed after a poll request is made before the scanner considers that request to have failed.
Number of Retries: 1-99. The number of retries the scanner will make when requesting data before reporting an error condition on the PV.
Snooper Response Time: 0.1 to 99.9 seconds. Time since the last PV update the before being considered an error.
Slave Timeout: 0.0 to 99.9 seconds. Time elapsed after the last data received from a master before the scanner considers the data to be out of date. Programming 0 disables the timeout, and PV data will be displayed indefinitely despite not being updated regularly.

Serial Communications

Protocol: Processes and displays data read from Modbus RTU slave devices. Up to 16 process variables (PVs) from up to 16 slave devices. Each PV programmed individually.
Scanner ID: 1 – 247. Specifies the address of the PD6730X.
Baud Rate: 1,200; 4,800; 9,600; 19,200; 38,400; 57,600; or 115,200 bps
Transmit Time Delay: Programmable between 0 and 199 ms
Parity/Stop Bit: Even, odd, none with 1 stop bit, or none with 2 stop bits
Byte-to-Byte Timeout: Max of 1.5 character times or 750 μs

Modbus Scanner Process Variables

PV Inputs: Up to 16 independently programmed Modbus process variables (PVs) may be scanned (Master mode) or detected (Snooper mode). Each of the 16 Modbus PVs may be enabled or disabled.
Slave ID: Specifies which device on the bus to monitor. Valid for Master and Snooper modes only.
Assign the slave ID or address (1-247) of each of the devices containing the process variables to be displayed (Slave ID for PV1-16).
Register Number: Specifies which register(s) to read in the devices on the bus. 
5 Digit Function 03: 40001–49999; 04: 30001–39999; or 65: 1–9999.
6 Digit Function 03: 400001–465535 or 04: 300001–365535; or 65: 1–65535.
Range is dependent on Function Code selection (03, 04, or 65)
Will read 2 registers for Long integer and Floating point data types; the register entered and the next consecutive register number.
Valid for Master and Snooper modes only.
Function Code: 03, 04, and 65 (used to read 32 bit registers). Master & Snooper modes only.
Data Type: Select the data format of the PVs. Select between short integer (2 byte), long integer (4 byte), or floating point (4 byte). Slave mode uses floating point only.
Byte Order: Integer data programmable as binary or BCD, and signed or unsigned. Byte order selectable as big-endian (1234), little-endian (4321), byte swap big-endian (2143), or byte swap little-endian (3412). Byte swap unavailable for short.

Math Channels

Math Result Channels: Four math channels CV1-CV4. Each math channel may be programmed for a math function.
Math Functions: Parameter 1 (PAR1), parameter 2 (PAR2), and parameter 3 (PAR3) independently programmable for each math channel C1-C4.

Math FunctionFunctionSettingAdditionPAR1 + PAR2SUMSubtractionPAR1 – PAR2DIFMultiplicationPAR1 * PAR2MULTIDivisionPAR1 / PAR2DIVIDEAbsolute DifferenceAbs(PAR1 – PAR2)DIFABSWeighted Average((PAR1 – PAR2)*PAR3) +PAR2WAVGDraw((PAR1 / PAR2) – 1) * PAR3DRAWRatio(PAR1 / PAR2) * PAR3RATIOConcentrationPAR1 / (PAR1 + PAR2) * PAR3CONCENConstantConstantCONSTLong IntegerConstantLONGFloating PointConstantFLOATNoneDisableNONEAbsolute ValueAbs(PAR1)ABSSquare Root√(PAR1)SQrt

Parameter Selection: Parameter 1 (PAR1), parameter 2 (PAR2), and parameter 3 (PAR3) selectable as: Modbus PV1-16, math channel C1-4, pulse input rate, total, grand total, or any math function.
Parameter Nested Math: Defining parameter 1 or 2 as a math function will prompt for level 2 parameter 1 (L2P1), level 2 parameter 2 (L2P2), and/or level 2 parameter 3 (L2P3). Level 2 parameters function identically as parameter 1 and 2 for nested math functions.

Pulse Input

Pulse/Transistor/Contact Closure Input: Field selectable; Sourcing or sinking pulse or square wave; 0-5 V, 0-12 V, or 0-24 V; TTL; NPN or PNP transistor; Open collector 100 kΩ pull-up to 3 V; Switch contact 100 kΩ pull-up to 3 V; PNP transistor 100 kΩ pull-down to ground (COM); Active input 100 kΩ to battery level, 10 kΩ to power
Maximum Frequency: 64 kHz; Minimum Pulse Width: 5 µs;

Threshold SettingLow (V)High (V)Normal1.22.0Low0.21.2

Opto-Isolated Input: Sourcing pulse or square wave 0-5 V, 0-12 V, or 0-24 V; Logic High: 2-24 V, Logic Low: < 1 V; Maximum Frequency: 20 kHz; Minimum Pulse Width: 20 µs; Input Current: 1 mA @ 5 V, 2.5 mA @ 12 V, 5 mA @ 24 V
Low Voltage Mag Pickup Input: Sensitivity: 20 mVp-p to 24 Vp-p; Maximum Frequency: 6 kHz
Minimum Input Frequency: 0.0001 Hz. Minimum frequency is dependent on high gate setting (rate display).
Input Impedance: Pulse input: Greater than 75 kΩ @ 1 kHz. Open collector/switch input: 100 kΩ pull-up to 3 V.
Accuracy: ±0.03% of calibrated span ±1 count
Pulse Input Recalibration: All ranges are calibrated at the factory to read frequency in Hz. No recalibration required.
Temperature Drift: Rate display is not affected by changes in temperature.
Low-Flow Cutoff: 0-99,999 (0 disables cutoff function)
Decimal Point: Up to four decimal places or none: 4.4444, 33.333, 222.22, 1111.1, or 00000
Calibration: May be calibrated using K-Factor, scale without signal source, or by applying an external calibration signal.
K-Factor: Field programmable K-Factor converts input pulses to rate in engineering units. May be programmed from 0.000001 to 9,999,999 pulses/unit.
Calibration Range: Input 1 signal must be ≥ 1 Hz; input 2 signal may be set anywhere above input 1 setting. Minimum input span is 1 Hz. An Error message will appear if the input 1 and input 2 signals are too close together.
Input Contact Debounce Filter: Programmable contact debounce filter. Input signal frequency speed selections of Hi (no filter), Med (250 Hz max input, 2 ms pulse width), and Low (100 Hz max input, 5 ms minimum pulse width).
Time Base: Second, minute, hour, or day
Time Base: Low gate: 1-99 seconds; High gate: 2-9,999 seconds

Pulse Rate/Totalizer

Display Assignment: The top display may be assigned to rate, total, or grand total, in addition to Modbus process variables. 
Rate Display Units: Gallons, liters, imperial gallons, cubic meters, barrels, bushels, cubic yards, cubic feet, cubic inches, liquid barrels, beer barrels, hectoliters, or custom.
Rate Display Time Base: Rate display may be calculated in terms of units per second, minute, hour, or day.
Total/Grand Total Display Units: Gallons, liters, imperial gallons, cubic meters, barrels, bushels, cubic yards, cubic feet, cubic inches, liquid barrels, beer barrels, hectoliters, or custom. Setting is independent for each.
Total/Grand Total Display Unit Multiplier: x1, x100 (h), x1000 (k), or x1,000,000 (M) multiplier (and prefix) applied to total or grand total display units. Setting is independent for each.
Total/Grand Total Decimal Points: Up to six decimal places or none: 
6.666666, 55.55555, 444.4444, 3333.333, 22222.22, 111111.1 or 0000000
Total and grand total decimal points are independently programmed, and are independent of rate decimal point.
Totalizers: Calculates total and grand total based on rate and field programmable multiplier to display total in engineering units. Time base must be selected according to the time units in which the rate is displayed. The total and grand total utilize the same time base, with different conversion factors and resets.
Totalizer Reset: Via SafeTouch® RESET button, mechanical button (cover off), external contact closure (total only), automatically via user selectable preset value and time delay (1 – 99,999 sec). Manual reset may be disabled or protected by password for the total and grand total. Total and grand total reset independently.
Total Overflow & Rollover: The total can display up to 9,999,999,999,999. Up to 9,999,999 can be displayed on the lower display normally. An overflow display will toggle between the first six digits and last seven digits (999999 <> 9999999) for a 13-digit total. The total will rollover beyond thirteen digits. The T indicator on the display will flash to indicate total overflow, and the six most significant digits (first six numbers of the total) are indicated with the flashing overflow symbol.
Grand Total Overflow & Rollover: The grand total can display up to 9,999,999,999,999. Up to 9,999,999 can be displayed on the lower display normally. An overflow display will toggle between the first six digits and last seven digits (999999 <> 9999999) for a 13-digit total. The grand total will rollover beyond thirteen digits. The GT indicator on the display will flash to indicate grand total overflow, and the six most significant digits (first six numbers of the grand total) are indicated with the flashing overflow symbol.
External Total Reset: External total reset connections are made between RST and COM. Logic High: 1.4 V, 3.3V max; Logic Low: < 0.8 V. 90 ms minimum pulse width.

4-20 mA Transmitter Output

Output Source: Modbus PV 1-16, math channel 1-4, rate/process, total, grand total, or disabled
Scaling Range: 4.000 to 20.000 mA for any display range.
Disable: If disabled, the output will output 3.2 mA
Calibration: Factory Calibrated: 0.0 to 1000.0 = 4-20 mA output
Underrange: Output Underrange: 3.8 mA
Overrange: Display Overrange: 20.5 mA. Output Overrange: 20.5 mA
Accuracy: ±0.05% span ±0.004 mA
Temperature Drift: 0.08 µA/°C max from -40 to 75°C ambient
External Loop Power Supply: 30 VDC maximum
Output Loop Resistance:

Power SupplyMinimumMaximum24 VDC10 Ω750 Ω30 VDC100 Ω1100 Ω

Note: loop-powered backlight subtracts 150Ω from maximum resistance figures above.

Open Collector Outputs

Output Assignment: Two open collector pulse outputs Out 1 and Out 2.
Individually programmable for Modbus PV, math channel, pulse rate, total, or grand total alarms; Modbus PV, math channel, pulse rate, total, or grand total pulse outputs; or retransmitting of pulse inputs; constant timed pulse output; quadrature outputs (requires Out 1 and Out 2); or off.
Rating: Isolated open collector, off: 24 VDC max, on: <1 V @ 150 mA max
Alarm Output: Assign to Modbus PV 1-16, math channel 1-4, or rate for high or low alarm trip point. Assign to total or grand total for total or grand total alarms.
Alarm Deadband: 0-100% FS, user selectable
Alarm Acknowledge: Front panel SCAN/ENTER button resets output and screen indication.
Pulse Output Count: The pulse output count (COUNT) is programmable from 0.000001 to 9999999. PV and math channels generate a frequency equal to the PV or math value divided by the Count value. Rate pulses are generated at a rate of one output pulse per Count value. Total and grand total pulses are generated for every total or grand total increment selected (e.g. Count value of 100 will generate one pulse every time the total is incremented by 100 units).
Pulse rate retransmission outputs one to one for input pulses, up to maximum output speed. Count is not used for retransmitting outputs.
Pulse Output Pulse Width: Unless otherwise stated, pulses are 50% duty cycle for required frequency.
A pulse rate retransmit output will generate 100 to 130 μs pulses at the falling edge of every input pulse.
Pulse Output Maximum Frequency: 5 kHz, pulse width at 50% duty cycle. If the outputs exceed 5 kHz, the scanner will display pUlse OVERRNG
Quadrature Output: Output set to quadrature will lag the other pulse output by 90° (1/4 duty cycle) at output frequency. Minimum 1 Hz
Timer Output: Programmable on and off time, repeating cycle. Minimum period 0.1 second, maximum 100,000 seconds. Minimum pulse time 0.01 second, maximum 10,000 seconds.

Applications

Modbus Scanner Example 1: Master Tank Level Indicator

The following example shows just one possible use for the PD6730X. The PD6730X is set up for Master mode, and is polling the Modbus transmitters. In this application we have a system consisting of (4) MTS M-Series multivariable tank level gauges connected to a PD6730-AX0-I-L displaying product level and interface level in feet and inches, and average temperature in °F. The tank level indicator displays the level and interface for each tank as the PVs are scanned.

Modbus Scanner Example 2: Snooper Flowmeter Display

In this application, a system consisting of (2) Modbus enabled flowmeters are connected to a SCADA system operated out of a control room. A Modbus PLC polls the data out of the flowmeters. A PD6730-AX0-I-2 has been added to the system as a Modbus Snooper, to provide the operators an easy to read field display near the flow lines. The scanner displays one flow rate on the top display, and one on the bottom display. Each has an alternating tag and unit for clear identification.

Connections

CodeDescriptionD+RS-485 data B (non-inverting)D-RS-485 data A (inverting)GRS-485 shield groundP+DC power positive terminalCOMDC power return/negative, reset contact closure commonRSTContact closure reset pull-up to 1.8 VDCS+Signal input positive terminalS-Signal input negative terminalOC1+Open collector output 1 positive terminalOC1-Open collector output 1 negative terminalOC2+Open collector output 2 positive terminalOC2-Open collector output 2 negative terminalLP+4-20 mA transmitter DC power positive terminalLP-4-20 mA transmitter regulated current output terminal

Dimensions

Data Sheet: Precision Digital PD6730X Data sheet
Instruction Manual: Precision Digital PD6730X Instruction Manuals