The Precision Digital ProtEX-RTA PD6820 is an explosion-proof, loop-powered flow rate/totalizer that can display flow rate and total from an analog output (4-20 mA) flowmeter. The fact that this meter is loop-powered means that there is no need to run additional, costly power lines into a hazardous area. The display has a five digit upper display for rate, a seven alpha-numeric character lower display for total, and comes standard with a backlight. Like all ProtEX products, the PD6820 explosion-proof flow rate/totalizer carries FM, CSA, ATEX, and IECEx approvals for use in hazardous areas. Two features that really make this flow rate/totalizer stand out are a wide viewing angle display and SafeTouch® through-glass buttons. These buttons allow the PD6820 to be programmed and operated through the glass, thus eliminating the need to remove the cover in a hazardous area.
Precision Digital PD6820 Loop-Powered Flow Rate Totalizer
- 4-20 mA Input
- Loop-Powered Flow Rate/Totalizer
- 1.5 Volt Drop (4.7 Volt Drop with Backlight)
- Display Rate & Total Simultaneously
- Loop-Powered Backlight with Red Backlight for Alarm Conditions
- NEMA 4X, IP65 Front
- -40 to 158°F (-40 to 70°C) Operating Temperature Range
- Free PC-Based USB Programming Software
- 5-Digit Alphanumeric Top Line
- 8-Digit Alphanumeric Bottom Line
- 8-Digit Total & Grand Total Display, Up to 13 Digits Using Both Lines
- 20-Segment Bargraph with Numeric Percent Indication
- Conformal Coated PCBs for Dust & Humidity Protection
- Two Open Collector Outputs Standard
- Dual-Line Display
- 1/8 DIN Shallow Depth Case
- Optional Loop-Powered Solid State Relays
- Optional 4-20 mA Analog Output
- UL & C-UL 61010 Listed for Electrical Safety
- UL & C-UL Listed as Intrinsically Safe and Nonincendive
- ATEX and IECEx Certified as Intrinsically Safe
The Loop Leader’s display provides multiple ways to help users understand and keep track of their processes. The most obvious is the dual line which typically allows the user to display both flow rate and total at the same time. There is also a bargraph that includes a numeric value of the percentage the bargraph represents. Finally, to alert users to an alarm condition, the display can turn red and flash an alarm message.
Display Flow Rate & Total at Same Time
One of the key features of the Loop Leader Flow Rate/Totalizers is their ability to display flow rate and total at the same time. In addition, the meter can toggle between the rate and total and their corresponding units.
Toggle Flow Rate and Rate Units on Top,
Toggle Total Flow and Total Units on Bottom
Wide Variety of Display Capabilities
In addition to the most common setup of flow rate on the top line and flow total on the bottom line, these meters can be set up for a variety of display configurations.
Display Flow Rate and Toggle Between Units & Tag
The following table shows the items that can be displayed on the Top and Bottom lines:
Top Line Can Display:Off (Blank)Preset batch valueRateStopwatchRate and its units alternatingTimers OC and relaysTotalMinTotal and its units alternatingMaxTagMin & MaxUnits
Bottom Line Can Display:Off (Blank)Units for value on top lineTotal (with units or tag alternating)TagTotal, its units, and the rate and units alternatingPreset batch valueGrand total (with units or tag alternating)Tag and rate units alternatingGrand total, units, and rate units alternatingTag and total units alternatingRate (with units or tag alternating)Rate’s percentage of max scaleRate and the total’s units alternatingmA input valueRate or total unitsmA output value
Commas on 8-Digit Totalizer for Easy Reading
It may seem like a simple thing, but adding commas to an eight-digit number makes it easier to read:
Bargraph Provides Quick Understanding
To help users get a quick understanding of where their process is at, certain Loop Leader skus are available with a 20-segment bargraph. This bargraph also includes a numeric value of the percentage the bargraph represents. The bargraph can be programmed to represent either the rate or total or it can be disabled.
Bargraph Based on Total
Alarms Indicated by Flashing Red Messages
When an alarm occurs, the Loop Leader’s display can be programmed to turn red and flash an alarm message along with the process variable and an alarm indicator (!). (Alarm indicator symbols are not available on bargraph skus) The Loop Leader’s flashing red alarm message can be activated even if no relay or open collector is connected.
Change Between Units without Needing to Re-Scale the Meter
It is possible to change the display units within the selected unit class without the need to re-scale the meter. When selecting a new unit from within the DISPLAY menu (e.g. changing from gallons (GAL) to liters (L)), the meter will automatically convert the display values to display the new unit. If entering a custom unit (CUSTM), a custom conversion factor will need to be entered.
Predefined and Custom Units
The meter has six available preprogrammed unit classes, volume, height, temperature, pressure, weight, and rate. When the desired unit class or unit of measure within a class is not available, a custom unit may be programmed by using the (CUSTOM) menu.
The max & min readings (peak & valley) reached by the process can be displayed either continuously or momentarily:
- Display momentarily by pressing the F1 key (default) or assigning to any of the other function keys or to the digital input in the User menu. Press Enter to lock/unlock max/min display.
- Display continuously by assigning either display line to max/min through the Display menu.
Any of the F1-F3 function keys (buttons) and the digital input can be programmed to reset the max & min readings.
Dual-Scale Display Feature
Users can use the Loop Leader’s dual-scale feature when they want to show the same input in two different scales. For instance, an application where the Loop Leader displays the input in gallons per minute and cubic feet per minute.
Rate in GPM on Top, Rate in CFM on Bottom
Loop Leaders are available with two open collector outputs as standard and two solid state relays and 4-20 mA output as options. The open collector outputs and relays generally operate in the same manner, with the major exception being the open collectors are not available for batch control or sampling and the relays are not available with pulse features. The open collectors and relays can be controlled either automatically or manually. The alarm status (with flashing red message) will show on the display even with no output wired.
Two Open Collector Outputs
The Loop Leader is equipped with two NPN open collector outputs that may be set up for pulse outputs, alarms, timed pulses, stopwatch on/off, or disabled. Pulse outputs can be set to transmit the rate, total or grand total. Output 2 may be used to generate a quadrature output based on the other open collector output. An output test mode is also selectable to generate pulses at a constant programmable frequency. The open collectors are commonly used to generate a pulse for every user-defined amount of flow that has been generated. For instance, the Loop Leader can be programmed to generate a pulse for every 100 gallons of flow.
Two Optional Solid State Relays
The meter is optionally equipped with two solid state relays that may be set up for alarms, timer, stopwatch on/off, sample or batch control. The relays are rated at 250 VAC/DC @ 1 A for resistive loads and 75 VA @ 0.6 A, 250 VAC/DC max (Safe Area only) for inductive loads. Alarms are available based on the rate, total, grand total, or digital input.
A relay set to sample will trigger when the total or grand total value has incremented by a programmed amount. The relay can be programmed to stay on for a specified amount of time. For example: if a relay is set to sample the total with a COUNT of 1,000 and a TIME of 10 seconds, the relay will energize for 10 seconds each time the total increments by 1,000 (e.g. 1000, 2000, 3000).
Optional Isolated 4-20 mA Output
The isolated analog output signal can be configured to represent the rate, total or to retransmit the 4-20 mA signal input without the need to scale the output. While the output is nominally 4-20 mA, the signal will accurately accommodate under- and over-ranges from 1 to 23 mA. The output can be reverse scaled such that the meter’s high calibration value outputs 4 mA and the meter’s low calibration outputs 20 mA.
Resetting the Open Collectors and Relays
The open collectors and relays (alarms) may be programmed to reset in the following ways:
- Automatic (AUTO): Alarm will reset automatically once the alarm condition has cleared.
- Automatic/Manual (AUTO.MAN): Alarm will reset automatically once the alarm condition has cleared but can also be reset using the Enter button (or whichever function key is set to acknowledge) at any time.
- Latching (LATCH): Alarm must be reset manually and can be done so at any time. Press the Enter (ACK) button at any time to clear the alarm.
- Latching with Reset after Cleared (L-CLEAR): Alarm must be reset manually and can only be done so after the alarm condition has cleared. Press the Enter (ACK) button after the alarm condition has cleared to reset the alarm.
Loop Leader flow rate/totalizers can be programmed for a wide variety of totalizer applications. They can display total, grand total, or non-resettable grand total; the rate can be displayed with a time base of seconds, minutes, hours or days. The user can program a totalizer conversion factor, a non-resettable grand total, password protection, and several total reset methods.
8-Digit Total & Grand Total Display, Up to 13 Digits Using Both Lines
The Loop Leader flow rate/totalizer can be programmed to show eight full digits of total on the bottom display or 13 digits of total using both the top and bottom displays. In both cases, the display can be programmed to include commas to make it easier to read the very large numbers; e.g. 44,987,356
In 13-digit mode, the bottom line shows the least significant digits and the top line shows the most significant digits. The meter is not capable of displaying commas on the top line, so this number is actually 1,211,230,379. The comas can be removed from bottom if desired. See sample on bottom, right.
Totalizer Conversion Factor & Multiplier
The user can enter a totalizer conversion factor that allows the meter to display total in different units than the rate. For instance, a customer could measure flow rate in gallons per minute and total in hundredths of acre-feet. A multiplier may be selected to automatically display the value in kGAL, MGAL, etc.
Totalizer Password Protection
The total and grand total can be password protected so they can be reset only by authorized personnel.
Non-Resettable Grand Total
The user can set up the grand total to be non-resettable by selecting YES for PERMLOCK in the Advanced – Grand Total – Reset menu. Once this is done, the grand total can never be reset.
Remote Total Reset
The total can be reset via an external contact closure on the digital input.
Front Panel Total Reset
The three front panel function keys can be programmed to reset the total and grand total. This makes it possible for the user to reset either the total or the grand total by pressing the appropriate function key. Of course, if the total or grand total is password protected, they will not reset when the function key is pressed unless the password is entered.
The user may program the meter for a low-flow cutoff such that the meter displays zero below this point, regardless of the input value.
The Loop Leader’s two relays can be set up to alarm when the total reaches a user-defined set point. A variety of reset modes are available and the user can also program time delays and fail-safe operation.
All versions of these instruments are CE marked. The hazardous area versions of these instruments are UL and C-UL Listed as intrinsically safe and nonincendive and ATEX and IECEx Certified for Intrinsic Safety in Hazardous Areas (Gas Atmospheres). These versions are also UL and C-UL Listed under the UL 61010-1 General Safety Standard.
One of the most useful aspects of the hazardous area approvals is that these instruments are approved by UL as nonincendive so they can be installed in Division 2 areas with no additional protective devices needed.
Except where noted all specifications apply to operation at +25°C.
Input: 4-20 mA
Accuracy: ±0.02% of span ±1 count, Square root and programmable exponent: 10-100% FS
Voltage Drop: Without backlight: 1.5 V maximum,
With backlight: 4.7 V maximum
Equivalent Resistance: With backlight off: 75 Ω @ 20 mA
With backlight on: 225 Ω @ 20 mA
Input Overload: Over current protection to 1 A maximum
Temperature Drift: 25 PPM/°C from -40 to 75°C ambient
Function: Linear, square root, or programmable exponent
Low-Flow Cutoff: 0.0 to 999,999.9
HART Transparency: Analog input will not interfere with existing HART communications on the wired 4-20 mA signal
Display: Dual-line LCD with backlight. Both lines 14-segment alphanumeric. Top: 0.7″ (17.8 mm), Bottom: 0.4″ (10.2 mm). Display may be programmed to turn red and flash a user-defined message on alarm condition.
Backlight: Powered by 4-20 mA loop. Intensity varies with signal level
PD6622 & PD6626:
Top line: 5 digits (-9999 to 99999) or 5 characters (all capital & most lower case letters)
Bottom line: 8 digits (-9,999,999 to 99,999,999; separated by commas) or 8 characters (all capital & most lower case letters)
PD6624 & PD6628:
Top line: 5 digits (-9999 to 99999) or 5 characters (all capital & most lower case letters)
Bottom line: 8 digits (-9,999,999 to 99,999,999; separated by commas) or 8 characters (all capital & most lower case letters)
Bargraph: 20 segments, numeric percent indication at top
Decimal Point & Commas
Top line: Up to four decimal places
Bottom line: Up to seven decimal places and commas to indicate 1000s (i.e. 88,987,628)
Dual-Scale Feature: The input can be displayed in different scales on the top and bottom lines. For instance, the top line could display the flow in GPM and the bottom line could display that same input in CFM.
Alarm Indication: Red backlight, flashing display, alarm symbol (!); Symbols are not available on bargraph skus.
Alarm Message: On or Off; user programmable, 8 characters maximum. Displayed every 10 seconds for 1 second on bottom line.
Display Update Rate: Ambient > -10°C: 1 update/second
Ambient -20°C: 1 update/2 seconds
From -20°C to -40°C the update rate slows down 1 second for every -2°C (e.g. at -24°C, 1 update/4 seconds).
Overrange: Top: 99999; Bottom: 99,999,999 (flashing)
Underrange: Top: -9999; Bottom: -9,999,999 (flashing)
Environmental: Operating temperature range:
-40 to 75°C for safe area products
-40 to 70°C for hazardous area products
Storage temperature range: -40 to 85°C
Relative humidity: 0 to 90% non-condensing. Printed circuit boards are conformally coated.
Programming Method: Front panel & Free PC-based USB programming software
Enclosure & Materials: Enclosure: 1/8 DIN, IP65, NEMA 4X front panel, high impact plastic, NORYL® polyphenylene ether & polystyrene blend (PPE PS) resin, UL 94V-0, Color: gray, Gasket: silicone rubber, Faceplate: LEXAN® polycarbonate (PC) film, Buttons: silicone rubber
Noise Filter: Averages the input signal over a period of time between 1 and 16 seconds to dampen the effects of a noisy signal that causes a jumpy display.
Recalibration: Recalibration is recommended at least every 12 months.
Max/Min Display: Max/min readings reached by the process are stored until reset by the user or until power to the meter is turned off.
Password: There are three password types available: Main, Total, and Grand Total. The Main password prevents access to the meter Programming Mode. Total and Grand Total passwords prevent resetting the total and grand total, respectively.
Non-Volatile Memory: All programmed settings and total and grand total values are stored in non-volatile memory for a minimum of ten years if power is lost.
Normal Mode Rejection: 64 dB at 50/60 Hz
Connections: Removable screw terminals accept 12 to 22 AWG.
DI Digital Input Contacts: 2.1 VDC on contact. Connect normally open contacts across DI+ and DI
DI Digital Input Logic Levels: Logic High: 2.4 to 30 VDC (max)
Logic Low: 0 to 0.9 VDC
Tightening Torque: Screw terminal connectors: 4.5 lb-in (0.5 Nm)
Mounting screws: 8.0 lb-in max. (0.9 Nm)
Overall Dimensions: 4.68″x 2.45″x 3.79″ (119 mm x 62 mm x 96 mm) (W x H x D)
Weight: 8.7 oz (247g) with option board
Warranty: 3 years parts and labor
Rate Display Capability: Top display: -9999 to 99999; bottom display: -9,999,999 to 99,999,999 (with commas)
Total Display Capability: Top display: -9999 to 99999; bottom display -9,999,999 to 99,999,999 (with commas)
Grand Total Display Capability: Top display: N/A; bottom display -9,999,999 to 99,999,999 (with commas)
13-Digit Total & Grand Total Capability: Up to 9,999,999,999,999 using both lines with 13-digit total feature enabled.
Total & Grand Total Indication: On bottom display; “T” indicates total and “GT” indicates grand total. (not available on bargraph skus)
Total Decimal Point: Up to four decimal places on top, up to seven decimal places on bottom. Total decimal point is independent of rate decimal point.
Totalizer: Calculates total based on rate and rate units to display total in engineering units. A custom factor must be programmed if using custom defined units.
Time Base: Seconds, Minutes, Hours, Days
Totalizer Rollover: Totalizer rolls over when display exceeds 99,999,999 (9,999,999,999,999 if 13-digit limit enabled). Relay status reflects display.
Total & Grand Total Reset: Via front panel button or external contact closure on digital input
Total & Grand Total Reset Passwords: Total and grand total passwords may be entered to prevent resetting the total or grand total unless a password is entered.
Non-Resettable Grand Total: Grand total reset may be disabled through the meter interface. Grand total reset may be permanently disabled by selecting YES at the PERMLOCK menu.
Caution: Once the Grand Total has been programmed as “non-resettable” the feature cannot be disabled
Common Open Collector & Relay (Alarm) Specifications
High or Low Alarm: User programmable for high or low alarm
Alarm Deadband: 0-100% FS, user programmable
On & Off Time Delay: 0 to 9,999 seconds
Fail-Safe Operation: Independent for each open collector and relay
Alarm Operation: Automatic, Automatic with manual override, Latching (manual reset anytime), Latching with reset after cleared (manual reset only after alarm has cleared)
Alarm Indication: Red backlight, flashing display, alarm symbol (!) (symbols not available on bargraph skus)
Alarm Message: On or Off; User programmable, 8 characters maximum. Displayed every 10 seconds for 1 second on bottom line
Alarm Acknowledge: Front panel ACK button or external digital input resets output and screen indication
Auto Initialization: When power is applied to the meter, open collectors and relays will reflect the state of the input to the meter.
Timer Output: One-shot or Continuous
Off Time Delay: 1 sec to 99:59:59 (hrs:min:sec)
On Time: 1 sec to 99:59:59 (hrs:min:sec)
Stopwatch: Output turns on when started and off when stopped
Open Collector Outputs
Rating: Two NPN, Isolated open collector, 30 VDC @ 150 mA max
Output Assignment: Pulse, Alarm, Timer, Total Reset, Stopwatch on/off, or Disable
Pulse Output Source: Rate, Total, Grand Total, or Test Frequency
Pulse Output Factor: 0.000001 to 999,999.9
Pulse Width: 0.5 ms @ 1 kHz; 500 ms @ 1 Hz; 50% duty cycle
Pulse Output Frequency: 1,000 Hz maximum
Quadrature Pulse Output: Available for Output 2 (90° behind Output 1)
Alarm Output Source: Assign to Rate, Total, Grand Total or Digital Input
Solid State Relays
Rating: Resistive Load: 250 VAC/DC @ 1 A
Inductive Load: 75 VA @ 0.6 A, 250 VAC/DC max (Safe Area only)
Noise Suppression: Metal oxide varistors across outputs
Relay Assignment: Alarm, Sample, Timer, Batch, Stopwatch on/off, or Disable
Alarm Output Source: Assign to Rate, Total, Grand Total, or Digital Input
4-20 mA Transmitter Output
Accuracy: ±0.05% FS ±0.001mA
Output Source: Rate, total, re-transmit; reverse scaling allowed
Scaling Range: 1.00 to 23.0 mA
Disable: High impedance state, less than 1 mA
Calibration: Factory calibrated 4.00 to 20.00 mA
Underrange: 1.0 mA, 3.5 mA, or 3.8 mA (If input < 3.5 mA), or Off; user selectable
Overrange: 20.5 mA, 20.8 mA, or 23.0 mA (If input > 20.5 mA), or Off; user selectable
Isolation: 500 V input-to-output
Temperature Drift: 0.5 μA/°C max from -40 to 75°C ambient
External Loop Power Supply: 7.0 VDC to 30.0 VDC maximum
Output Loop Resistance: 10-750 Ω @ 24 VDC; 100-1100 Ω @ 30 VDC
Methods: Automatic or Manual, count up or count down
Manual Batch Start: Pressing F1 function key starts the batch
Manual Batch Pause/Stop: Pressing F3 once pauses the batch, pressing it twice cancels the batch
Automatic Batching: The Loop Leader can be used as an automatic batch controller where batches run continuously without operator input.
Batching Relay Operation: Single or dual-relay batching with optional preclose for dual-stage operation
Batch Preset: Set via F2 function key anywhere between 0.0001 to 99,999 based on batch total decimal point. If batch total is assigned to bottom, the preset can be up to 8 digits.
Batch Preclose: For two-stage batch application, a preclose value can be set to close the main flow line.
Automatic Batch Restart Delay: 1 to 9,999 seconds. The batch will automatically restart after completion of the last batch.
Hazardous Area Approvals
ATEX: II 1G, Ex ia IIC T4 Ga, Ta = -40°C to +70°C
Certificate number: CML 17ATEX2015X
IECEx: Ex ia IIC T4 Ga, Tamb = -40°C to +70°C
Certificate number: IECEx CML 17.0008X
UL & C-UL Listed as Intrinsically Safe and Nonincendive:
Class I, Division 1, Groups A, B, C and D T4,
Class I, Division 2, Groups A, B, C and D T4
Ex ia IIC T4 (Canada); Class I Zone 0, Zone 1
AEx ia IIC T4 (U.S.)
Class I Zone 2, Group IIC T4 (U.S.)
PROCESS CONTROL EQUIPMENT FOR USE IN HAZARDOUS LOCATIONS
UL & C-UL 61010 Listed for Electrical Safety and Type 4X Environmental:
Standards for Safety:
IEC 61010-1:2010 (3rd Edition);
UL 61010-1, 3rd Edition;
CAN/CSA-C22.2 No. 61010-1-12, 3rd Edition;
Free Meterview XL PC-Based Programming Software
The main screen displays an image of the connected meter and includes various information about this meter, such as sku number, readings, and status.
Free, PC-based, MeterView XL software that connects to the meter via a micro USB cable is available for programming and setup of the meters. This software greatly simplifies the programming process and also allows the user to save configuration files for later use. The meter will also be powered by the USB connection so no additional power is needed during programming.
- Easiest Way to Program Your Loop Leader
- Convenient USB Connection
- Meter Powered by USB Connection During Programming
- Save & Print Configuration Files without Meter Connected
- Micro USB Cable Provided
- Panel cutout required: 1.772″ x 3.622″ (45mm x 92mm)
- Panel thickness: 0.040 – 0.250″ (1.0mm – 6.4mm)
- Mounting brackets lock in place for easy mounting
- Clearance: Allow 6″ (152 mm) behind the panel
Open Channel Flow
The PD6622/24, in combination with an ultrasonic level transmitter, makes for an economical way to measure and display open channel flow rate and total in most weirs and flumes and take periodic samples.
Differential Pressure Flow
The PD6622/24 can display flow rate and total by extracting the square root from the 4-20 mA signal from a differential pressure transmitter. The user selectable low-flow cutoff feature gives a reading of zero when the flow rate drops below a user selectable value.
- Display Flow Rate
- User Selectable Low-Flow Cutoff
- Only 2 Calibration Points Required
The Loop Leader, when ordered with the two solid state relays, can be used as a simple, one or two-stage batch controller. The user enters a preset and preclose value and sets the Loop Leader to either count up or count down. The top display will show the total and the bottom display will show the preset batch amount. The function keys are automatically changed so that F1 starts a batch, F2 opens the preset menu to allow the preset value to be changed, and F3 pauses/stops the currently running batch. Batching can be either automatic or manual.
The following shows the Loop Leader performing a manual batch operation:
Both valves are closed with an empty barrel in place. The batched total is displayed in the top display, the preset is selected for the bottom display.
The START button (F1) is pressed. Both valves open. The barrel begins to fill.
When the batch total reaches a value of 50.00 (Preset [55.00] – Preclose [5.00]) the full-flow valve closes. The fill rate of the tank slows as a result.
When the batch total equals the preset amount, the restrictedflow valve closes. The barrel is now full.
After placing a new, empty barrel, a new preset fill amount may be selected with the Batch key (F2), while the process is stopped.
Begin New Batch
Press the START key (F1) and a new batch will begin. With both valves open, the process continues.
At any time, the STOP button (F3) may be pressed, once to Pause the process, or twice to cancel the batch, which stops the process.
Application Timers are used in everyday life; one of the most common examples is the microwave oven. Industrial timers are used in process control applications where certain events or actions need to be controlled by time. Examples include automatic and batch control applications, where the relay needs to be energized for a specific length of time.
The timer fuction is available on the open collector and relay outputs; which means that you can have up to four timers per meter. The start and stop actions can be triggered from the setup menu or by the function keys and digital input. The meter can be setup to display the off/on timer count down.
There are two modes of operation:
- Continuous Timer (Interval)
At the start of the timer the output is off and turns on after the Off Delay elapses. The output remains on for the duration of the On Time. The cycle repeats until the user stops the timer either from the menu or a function key.
- One-Shot Timer
At the start of the timer the output is off and turns on after the Off Delay elapses. The output remains on for the duration of the On Time. The timer stops and the cycle does not repeat.
- A sensor detects the bottle is in place and triggers the digital input to start the timer
- The timer output controls the filling pump
- The On Time is set according to the time needed to fill the bottle