E02 OCT Info

Definition

Sets the definition for the flow meter’s OCT operation. Default: Off.

Notes

  1. If E02 is set to “Pulse v2”, configure the pulse width in E03 Pulse Time and set the pulse reference unit in E14 Pulse v2 Unit.

  2. Flow alarms are configured via D05, D06, D07; Totalizer alarms via D08, D09, D10; Pulse v2 settings via E03, E14.

Operation Procedure

E02 OCT Info. Setting Steps
• From the main screen (green backlight), 
  press Orange Button (Setup) to enter settings (orange backlight).
• Use Gray Arrow Buttons to select E. Commute , press Orange Button (Enter).
• Use Gray Arrow Buttons to select E02 OCT Info., press Orange Button (Enter).
• Use Gray Arrow Buttons to choose the options. 
• Press Orange Button (Set) to confirm.
• Press Blue Button (ESC) to return to the main screen (green backlight).

E02 Options, RS485 Values, Read/Write Commands, and Formats

Options
RS-485 Value

Alarm a

0

Alarm a b

1

Alarm a b c

2

Over Flowrate

3

Over Total

4

Pulse 2.0

5

Off (Default)

6

Dosing

7

Refer to the Read/Write Memory List for the Modbus command format. This parameter uses the Int16 data format.

chevron-rightPulse Output – Pulse V2 Function (Click to Expand)hashtag

一、 Technical Principle: Pulse V2 “Batch Reporting” Mechanism

Pulse V2 differs from traditional continuous variable-frequency pulse output. It uses a periodic pulse burst mechanism. At the end of each update cycle, the system converts the accumulated flow into a burst of pulses and transmits them in a short period of time.

A19 Defines the “Reporting Cycle”:

  • A19 = 1.0 s (Default): Flow is accumulated every 1 second, and the corresponding pulse burst is transmitted during the following 1 second.

  • A19 = 0.5 s (High-speed): Flow is accumulated every 0.5 seconds, and the corresponding pulse burst is transmitted during the following 0.5 seconds.


2. Parameter Configuration Table

Parameter Code

Name

Function Description

Setting Recommendation

A19

Fast Update

Flow Calculation Cycle

1.0 s: Suitable for general PLC applications. 0.5 s: Suitable for high-precision or high-speed counting applications.

E02

OCT Definition

Output Mode Selection

Pulse V2 must be selected.

E14

Pulse Base Unit

Flow per Pulse

Determines the resolution (e.g., 0.1 represents 0.1 L/pulse).

E03

Pulse Width

Signal Duration

Determines whether the PLC can correctly capture the signal.


3. Core Steps: Settings Based on PLC Type

Option A: Connected to General PLC Input (Common DI)

  • Applicable for: PLCs without high-speed counting modules or with slow scan cycles (>10 ms).

  • A19 (Update Frequency): Recommended 1.0 s (updates once per second).

  • E14 (Resolution): Recommended large (e.g., 0.1 or 1.0).

  • E03 (Pulse Width): Recommended 50 ms.

  • Limitation: When the flow rate is high, the total number of pulses should not be too large, otherwise all pulses may not be transmitted within 1 second.

Option B: Connected to PLC High-Speed Counting Module (HSC)

  • Applicable for: Precise quantitative control and high-resolution monitoring.

  • A19 (Update Frequency): Can be set to 0.5 s (updates every 0.5 seconds).

  • E14 (Resolution): Can be set small (e.g., 0.01 or 0.001).

  • E03 (Pulse Width): Recommended 0.5 ms (default) or 1 ms.

  • Limitation: Although HSC can read high-frequency signals, it must still ensure that all pulses can be transmitted within 0.5 seconds.


4. Frequency Safety Check (Error Prevention Calculation)

To prevent signal overlap (“traffic jam”) that may cause the PLC to miss pulses, the following calculation should be performed: verify whether the pulse burst generated at maximum flow can be fully transmitted within the A19 reporting cycle.

1. Calculate the Number of Pulses per Cycle (N)

First, calculate the maximum number of pulses the flowmeter can generate within one update cycle:

N=(Maximum LPM/60)×A19 Cycle (s)E14 N = \frac{(\mathrm{Maximum\ LPM} / 60) \times \mathrm{A19\ Cycle\ (s)}}{E14}

2. Determine Safety Standard

To ensure sufficient spacing between pulses (recommended 50% duty cycle), the following condition must be met:

N×(E03×2)<A19cycle(s)N×(E03×2)< A19 cycle (s)

💡 Why multiply by 2?

A complete pulse cycle consists of high-level time (E03) and low-level interval time. To ensure stable detection by the receiving device (PLC), it is generally recommended that the interval time be at least equal to the pulse width.


Example Scenario Calculation

Assume the following site conditions and settings:

  • Maximum Flow: 60 LPM

  • A19 (Cycle Time): 1.0 s

  • E14 (Pulse Unit): 0.1 L/pulse

  • E03 (Pulse Width): 50 ms (0.05 s)

Step 1: Calculate Number of Pulses

N=(60÷60)×1.00.1=10 (pulse)N = \frac{(60 \div 60) \times 1.0}{0.1} = 10 \text{ (pulse)}

Step 2: Check Safety Standard

10×(0.05×2)=1.0s10 \times (0.05 \times 2) = 1.0\text{s}

Result Evaluation: The calculated transmission time is 1.0 s, exactly equal to the A19 cycle time. This indicates that the signal is at the “limit” state, with almost no extra spacing between pulses. If the actual flow exceeds 60 LPM, pulses may overlap, causing the PLC to miss counts.

Optimization Suggestions:

  • Option A: Increase E14 (e.g., set to 0.2) to reduce the number of pulses by half.

  • Option B: Decrease E03 (e.g., set to 20 ms) to shorten the duration of each pulse.


5. Troubleshooting

Q1: The panel shows flow, but the PLC does not receive any values

  • Cause A: E03 (Pulse Width) is set too short and is filtered out by the PLC. Solution: Increase E03 to 50 ms.

  • Cause B: E02 is not set to Pulse V2.

Q2: PLC misses counts or stops increasing at high flow rates

  • Cause: Signal overlap. Pulses are too wide and dense, causing the high-level signal to “stick” and form a straight line. Solution A: Increase E14 (e.g., 0.01 → 0.1) to reduce the total number of pulses. Solution B: Decrease E03 (e.g., 10 ms → 1 ms) to increase spacing between pulses.

Q3: PLC cumulative value does not match the flowmeter panel

  • Cause: Pulse frequency approaches the PLC’s sampling limit, causing occasional missed counts.

  • Solution: Increase E14 to use a larger pulse unit (e.g., change from 1 mL/pulse to 10 mL/pulse).

chevron-rightDosing Function (Click to Expand)hashtag

1. Flow Meter Dosing Function Description

The dosing function controls a valve based on the flow meter’s totalizer. When the accumulated volume reaches the preset target, the valve closes automatically. After the set buffer time, the totalizer resets to zero, preparing for the next dosing cycle.

This function enables dosing control directly through the flow meter without an external PLC, making it suitable for chemical dosing, liquid replenishment, and batching applications.

2. Parameter Configuration Table

Parameter Code
Function
Description
Recommended Setting

E02

OCT Definition

Sets the control output mode

Must be set to Dosing mode

C03

Dosing Mode

Enables the dosing function

Set to On

C04

Dosing Target

Sets the target volume per dosing cycle

Enter as required (unit: L)

C05

Dosing Reset Time

Sets the buffer time after the target is reached before reset

Set based on system response time (unit: s)

H09

Startup Screen

Sets the main display screen

Set to Dosing mode screen

D16

Dosing Alarm

Alarm indication when dosing is completed

Enable as required or set to Do Not Disturb

3. Dosing Operation

After the valve opens, fluid flow begins and the flow meter accumulates volume in real time. When the accumulated volume reaches the dosing target set in C04, the system closes the valve according to the OCT output logic defined in E02, completing the dosing cycle. A “Dosing Complete” alarm is then triggered based on the D16 setting.

The system then enters the reset delay defined in C05. Once the delay time elapses, the totalizer is automatically reset to zero and the system is ready for the next dosing cycle.

circle-info

Due to response time delays in valve actuation and control signals, the actual dosing result may differ slightly from the set value. This deviation becomes more noticeable with smaller dosing volumes, higher flow rates, or longer distances between the valve, flow meter, and container.

For higher dosing accuracy, select an appropriate pipe size and piping layout. It is recommended to perform on-site testing and adjust the calibration (scaling) factor as needed before actual operation.

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