1) Beam Pitch K vs. Minimum Detectable Size

Definition. K is the distance between adjacent beam centers in millimeters. Finer pitch samples the object more densely, but pitch, minimum detectable object, edge resolution and measurement accuracy are different specifications.

Feature check. There is no verified universal 1.2 × K object rule or 1.5 × K hole rule for these families. Ask for the exact model's detectable object and opening limits at the specified range and scan mode. Test the smallest target at different positions between beams, including expected vibration, alignment variation and material transparency. For gauging, compare repeated results with a reference measurement across the required working range.

The published DQL specification tables list K = 1.25, 2.5, 5, 10, 20, 40 and 80 mm; the DQM specification tables list 2.5, 5, 10, 20, 40 and 80 mm. Verify availability for the selected beam count. As a terminology example, Banner's EZ-ARRAY overview lists object detection and edge resolution separately; its values are not DQL/DQM ratings.

2) How to Size Measuring Height H

Measuring height must cover the target envelope along the array, including changes in object position and the installation tolerances. Set the margins from that application; one beam pitch at each end is not a universal allowance.

Beam-span formula. The published tables use H = (n − 1) × K, where n is beam count. This is the span between the first and last beam centers, not the transmitter-to-receiver range or overall housing length. For example, 32 beams at 2.5 mm pitch give H = 77.5 mm.

Select an available beam count that covers the required span, then check end offsets, mounting and connector clearance on the exact order drawing. The drawing below uses L = H + P + J + 30 mm; P and J vary with pitch. The DQL table and this drawing differ for some overall lengths, so neither L = H + 30 mm nor a family-wide fixed allowance is suitable for final mechanical design. Resolve the drawing revision with the supplier before making brackets.

3) Line Speed & Response Time Check

Detection requires sufficient object presence timeand, for counting separate items, sufficient gap presence time. These are distinct from the delay before an output or PLC value changes.

Geometric estimate. For an opaque object crossing an ideal thin beam at constant positive speed, let v be speed in m/s and s its length along travel in mm: t = s / (1000 × v) seconds. A 10 mm part at 1 m/s gives 0.010 s, or 10 ms. The transverse pitch K does not add to this travel length. Actual usable interruption time depends on aperture, geometry and the detection threshold; validate it on the sensor.

Timing evidence. Obtain minimum object/gap presence time and worst-case output response for the selected beam count, scan mode and filtering. The DQL catalogue states ≤15 ms with beam-count dependence. DAIDISIKE confirms a 0.5 ms response for all DQM specifications; this transistor-output response is not an end-to-end PLC update time or a guaranteed minimum object/gap duration. Do not assume 5 ms is conservative or that one response-time comparison proves reliable counting.

Allow separately for communication, input filtering and PLC capture. If the shortest event cannot be captured, slow the line or use a documented, validated faster configuration or capture method. Filtering can add delay or suppress short events; increasing transverse pitch does not lengthen their dwell time. SICK's light-grid speed check and timing definitions explain these distinctions for MLG-2; do not transfer its numerical limits or modes to DQL/DQM.

4) Quick Application Matrix (DAIDISIKE DQL/DQM)

This is a shortlisting matrix, not a guaranteed minimum-object or accuracy table. Validate samples, working distance and ambient light. The DQL catalogue lists RS-485 Modbus RTU and analog 4–20 mA / 0–10 V; confirm the ordered output and its scaling. DQM provides NPN or PNP transistor outputs for high-speed detection and counting, with no RS-485 or RS-232 interface. Do not assume a transistor signal supplies dimensions or beam-by-beam data; select the appropriate DQL interface if measured values are required.

1) Three Ways to Use a DQL/DQM in Your Line

2) Terminal Layout and Recommended Wiring

This is an interface checklist, not a terminal-number diagram. Obtain the supplied sensor drawing and the exact PLC/input-module instructions before wiring.

The DQM factory drawing distinguishes a five-core NPN version with one output from a seven-core PNP version with two outputs. Match the supplied configuration; do not specify every DQM as dual-channel. The drawing's OSSD labels do not establish a certified protective output or authorize personnel-safety use.

For an RS485 bus, follow the selected interface's requirements for a main trunk, stubs, end termination and polarization. Do not add bias resistors to every device or assume fixed 680 Ω values are suitable. Cable shield, signal reference and protective earth need an intentional EMC/grounding arrangement; neither “always one end” nor “always both ends” is a universal rule.

Serial settings: record the actual baud rate, unit address, parity, data/stop bits and timeout from the manual and configuration. The former 9600-8-N-1/address-1 example is not established as a universal factory default. Configure each device while preventing unintended machine operation.

3) Standard Modbus Register Map

Modbus standardizes transactions, not a universal sensor data map. DQM has no RS485 or RS232 interface, so this section is for serial-equipped DQL configurations, not DQM. The previous example addresses 40001–40021, model identifiers, status-bit meanings and 0xA55A reset command were not verified manufacturer instructions and must not be copied into a machine. Use this record to obtain the actual map for the supplied firmware.

Function 03 reads holding registers; 04 reads input registers; 06 writes one register; 16 (0x10) writes multiple registers, it is not a multi-register read. Only use functions supported by the device. Human-readable 4xxxx references and a library's zero-based protocol address are different conventions; confirm the conversion rather than sending 40001 blindly.

4) PLC and SCADA Platform Compatibility Checks

The following brands organize an interface review; this is not a claim of customer-tested compatibility across their entire product families. Confirm ports, add-on modules, protocol libraries, electrical isolation and timing for the exact controller.

If translation to PROFINET, EtherNet/IP, EtherCAT or Modbus TCP is required, select a gateway that explicitly supports both required sides and the data mapping. A generic serial adapter is not necessarily a protocol gateway. Include update delay and missing-data diagnostics in acceptance testing.

5) Analog Output Scaling — From AI Counts to Millimeters

First verify that the selected output represents a linear measured span, and establish the meaning of an unobstructed beam array. A clear field must not automatically be treated as the maximum measured object size.

value = engMin + (raw − rawMin) × (engMax − engMin) / (rawMax − rawMin)

• Take rawMin/rawMax from the exact input module and configured range, not from the PLC brand. A Siemens channel configured for 4–20 mA need not use the same counts as one configured for 0–20 mA.
• Illustration only: if 4–20 mA is explicitly configured to represent 0–500 mm linearly, 12 mA represents 250 mm. This does not prove the mapping, accuracy or zero state of any DAIDISIKE model.
• Keep invalid, under-range and over-range states separate from valid measurements; follow the transmitter and AI module diagnostics. Do not classify every value below one guessed count threshold as a broken wire.
• A 250 Ω shunt gives 1–5 V for 4–20 mA by Ohm's law, but its burden, tolerance, power rating and the input impedance must be acceptable. Prefer a suitable current input when that is the specified interface.

A current loop tolerates series resistance only within its available compliance voltage; it is not immune to voltage drop or ground-potential limits. Review isolation and maximum loop load. Filters add delay and can hide brief targets, so validate any averaging against the complete timing budget.

6) MES and Data-Logging Patterns

• PLC acquisition, MES reads tags: map the documented sensor values to PLC tags with units, validity and timestamp/age information. Use the plant's supported data interface to publish them.
• IPC acquisition: use a suitable isolated serial interface, a version-matched library and the actual device map. Record timeouts and exceptions, not just successful values.
• Edge-gateway publication: verify that the gateway supports serial Modbus acquisition and the required MQTT or other upstream protocol. Do not assume a vibration sensor or a general embedded computer supplies that function out of the box.

Calculate request/response length, baud rate, bus silence, device processing, retries and the number of units before assigning a polling rate. “600 cycles per minute at 9600 baud” is not a guaranteed lossless scan rate. A PLC or sensor event buffer may be needed for brief parts; increasing baud rate helps only where all devices support it and the complete process budget permits.

7) Commissioning Checklist for a New Line

1. Wire power and I/O. Use the exact model pinout and input-module manual; confirm supply, signal type, current limits and EMC arrangements before energizing.
2. Set serial parameters. For a serial-equipped model, record the documented address, baud rate, parity and stop bits; do not assume factory defaults.
3. Verify Modbus. Start with a documented read-only register and confirm address convention, response length, data type and scaling against a known sample.
4. Scale analog. For an analog-equipped model, use its measured-quantity mapping and the exact AI channel's configured raw range; check several reference points.
5. Log to MES. Record measurements with timestamps, units, quality flags and job identifiers; detect stale data, missing samples and communication faults.

• Verify differential-pair polarity from both manuals; CRC errors have several possible causes and do not by themselves prove reversed wires.
• Inspect cable topology, termination, reference and bonding against the interface design. Do not add resistors or swap conductors on an operating machine as a trial-and-error method.
• Compare known targets at several positions, orientations and line speeds. Agree acceptance tolerances from the application and actual device accuracy; one beam pitch is not a universal guaranteed error limit.
• Check output validity, communication loss, restart and any supported counter rollover. Never issue an unverified reset code.
• Budget optical acquisition, filters, I/O, communications and receiving-controller timing. Validate short targets; neither a guessed 5 ms delay nor twice the response time is a universal acceptance rule.
• Run an agreed sample plan and verify units, timestamps, job IDs, quality flags and missing samples in storage. A sample exercise is not evidence of an already completed customer test.

8) For Engineers — Reference Code Snippets

These pseudocode examples show the read/validate/log sequence only. They are not runnable PLC or Python drivers, do not assign real register addresses and contain no protective-control logic. Use the selected library's current API and test an approved, read-only mapping before production use.

(* Integration pseudocode, not vendor function-block syntax.
   No DAIDISIKE register addresses are assigned here. *)
IF DocumentedReadCompleted THEN
    IF ResponseValid AND ExpectedLength AND DataFresh THEN
        Measurement := DecodeUsingApprovedMap(Response);
        Quality := GOOD;
    ELSE
        Quality := INVALID;
    END_IF;
END_IF;
(* A timeout also sets INVALID. Never reuse stale data as a new sample.
   No write/reset commands and no protective-stop logic are shown. *)

# Logging design pseudocode, NOT an executable device driver.
# Select a supported library version and implement its actual API separately.
# read_documented_value() is a placeholder, not a DAIDISIKE SDK call.
sample = read_documented_value(approved_model_map)
record = {
    "timestamp_utc": synchronized_utc_time(),
    "value": sample.value if sample.valid else None,
    "unit": approved_model_map.unit,
    "quality": sample.quality,
    "job_id": current_job_id,
}
append_record(record)  # Define CSV headers/types and storage error handling.
# Preserve invalid/missing-sample information. Do not send register writes.

PLC/MES Integration Questions