Digital I/O Troubleshooting

Cannot Connect to Module

Diagnostic Steps:

1. Check Power
   • Sealevel: Power LED green?
   • WISE: Power LED on?
   • Measure voltage at terminals: 24VDC ±10%
2. Check Network
   • Cable fully seated in RJ45?
   • Link lights blinking?
   • Try different cable or switch port
3. Check IP Address
   • Sealevel default: 192.168.42.253
   • WISE default: 192.168.1.1 or DHCP
   • Is computer on same subnet?
4. Ping Module
   • Open command prompt
   • ping 192.168.42.253 (or module IP)
   • Should receive replies

Signal Not Detected

Diagnostic Steps:

1. Measure Voltage
   • Use multimeter
   • Measure between input terminal and common
   • Should read signal voltage when active
   • Should read near 0V when inactive
2. Check Wiring
   • Terminals tight?
   • Correct polarity?
   • Any broken wires?
3. Verify Modbus Address
   • Sealevel: AI0=register 0, Opto 1=coil 0
   • WISE: DI0=coil 0, DI1=coil 1, etc.
4. Test with Configuration Tool
   • Sealevel: Use MaxSSD utility
   • WISE: Use web interface diagnostics
   • Confirm signal reaches module

Current Transducer (CT) State Detection Issues

Current transducers measure electrical current to determine machine state (Active/Idle). Use this systematic approach to diagnose and resolve CT-related issues.

Common Symptoms:

• Machine shows Idle while physically running
• Machine shows Active while physically idle
• Erratic switching between Active and Idle states
• Machine state never changes

⚠️ CRITICAL PRINCIPLE: When a machine is completely idle (spindle off, no motors running), the CT voltage should be very low (typically 0.5V - 1.5V). If you see high voltage during idle, the CT is in the wrong location or measuring the wrong circuit.

Understanding CT Switch Positions

Most analog CTs (0-10V output) have three switch positions that determine the current measurement range:

Switch Position	Current Range	When to Use
1 (Low)	0-50A	Small motors, low-power equipment
2 (Medium)	0-100A	Most spindle motors, typical CNC equipment
3 (High)	0-200A	Large motors, high-power machines

How to Choose: Check the motor nameplate for rated current, then select the switch position that covers that range. Too low = CT maxes out; too high = poor signal separation.

Diagnostic Steps:

1. Review Current Configuration

   • Navigate to Machines → [Machine] → Settings → Data Collection
   • Document current threshold value and off-delay setting

2. Observe CT Behavior in Timeline

   • Go to Machine → Timeline view and enable Live Mode
   • Add "CT Converted Voltage - Raw" data item to timeline
   • Watch the signal for several minutes while machine cycles

3. Verify Physical Installation

Checkpoint	✅ Correct	❌ Incorrect
Clamp closure	Fully closed, no gap	Gap visible between halves
Cable type	Single conductor only	Multiple wires or cable bundle
Location	Spindle motor or main power	General building power
Interference	18"+ from VFDs/transformers	Adjacent to high-voltage equipment

4. Perform Live Testing (Most Critical Step)

Stand at the machine and observe CT voltage during these states:

Test A: Machine Completely Idle

• Spindle OFF, no motors running
• Record idle voltage range (should be < 2.0V)
• If higher: CT is on wrong circuit or switch position too high

Test B: Spindle Running (Not Cutting)

• Start machine, activate spindle at normal speed
• Record active voltage range

Test C: Production (Cutting)

• Load part and begin cutting operation
• Record cutting voltage range

5. Calculate Optimal Threshold

Optimal Threshold = (Max Idle Voltage + Min Active Voltage) / 2

Example:

• Idle range: 0.8V to 1.5V (Max = 1.5V)
• Active range: 3.2V to 5.0V (Min = 3.2V)
• Calculation: (1.5 + 3.2) / 2 = 2.35V
• Set threshold to 2.3V or 2.5V

⚠️ Important: You need at least 0.5V separation between max idle and min active.

6. Update Adapter Script Configuration

Navigate to Machines → [Machine] → Settings → Data Collection and update your adapter script:

variables:
  # Intermediate variable for logic (not output)
  ct-voltage-int:
    - source: spindle-raw / 409.6 # SeaLevel conversion

  # Cleaned variable for data output
  ct-voltage:
    - source: ct-voltage-int
    - resample: 0.5 # Sample every 0.5 seconds
    - min-delta: 0.1 # Only send if changed by 0.1V

  # Execution state based on threshold
  execution:
    - source: ct-voltage-int > 2.5 # Your calculated threshold
    - off-delay: 90 # Optional delay in seconds
    - state:
        - ACTIVE: this
        - READY: true

data-items:
  - execution
  - ct-voltage # Output cleaned variable only

⚠️ CRITICAL Variable Naming:

• Always use TWO variables for CT voltage
• Intermediate variable (ct-voltage-int): Used for threshold logic, never include in data-items
• Cleaned variable (ct-voltage): Uses resample and min-delta to reduce noise, safe for data-items
• This prevents database overload from noisy analog signals

Common CT Issues & Quick Solutions:

No voltage signal (flat line at 0V)

• Check physical connections at IO module
• Verify Modbus register address in script
• Test with multimeter or swap CT

Constant high voltage (even when machine is off)

• Turn machine off at breaker - CT should drop to ~0V
• If signal persists, CT is on wrong circuit
• Relocate to machine-specific circuit (spindle motor)
• Ensure only single conductor in CT clamp
• Check CT switch position - try higher range setting

Extreme noise / erratic signal

• Move CT 18"+ away from VFDs and transformers
• Reroute CT cable away from high-voltage runs
• Verify cable shielding is intact

Typical Voltage Ranges (Quick Reference):

Machine State	Typical Voltage	Diagnosis
Completely Off (breaker off)	0V - 0.2V	No current flowing
Idle / Standby	0.5V - 1.5V	✅ Normal baseline
⚠️ High Idle (PROBLEM)	2.5V - 4.0V	❌ Wrong circuit or multiple conductors
Spindle Running (no load)	2.5V - 4.0V	Clear increase from idle
Cutting / Under Load	3.5V - 5.0V	Peak activity

When to Contact Support:

• No voltage signal despite verified connections
• CT signal doesn't correlate with machine behavior
• Overlapping idle/active voltage ranges after relocating CT
• Adapter script changes don't take effect

Include: Machine name, Timeline screenshots showing CT voltage, documented voltage ranges, photos of CT installation, and current adapter script.

False Part Counts

Solutions:

1. Add Auto Mode Logic

   part-count:
     - source: part-signal and auto-mode
     - rising-edge
     - count

2. Add Pulse Duration Verification (for coolant method)

   filtered-signal:
     - source: raw-signal
     - min-delta: 0.4
     - max-delta: 0.7

3. Use Correct Edge Detection

   • Try rising-edge vs falling-edge
   • Depends on signal behavior

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Best Practices

Planning:

• Study machine operation before selecting signals
• Review electrical schematics
• Test signals under various conditions
• Document everything

Current Transducers:

• Use analog 0-10V CTs for Sealevel eI/O-170 analog inputs
• Use dry contact CTs for Sealevel eI/O-170 digital inputs (Opto 1/2)
• Clamp around ONE phase only
• Secure CT to prevent vibration
• Set low threshold (1.0-1.5V) for low-speed detection

Wiring:

• Use 18-22 AWG stranded wire
• Label all wires clearly
• Keep wiring neat and organized
• For Sealevel digital inputs: DO NOT apply external voltage (internally powered)

Electrical Safety:

• Never apply >50VDC to any input
• Use relays for AC voltages
• Verify voltage with multimeter
• Follow lockout/tagout procedures
• Work with qualified electricians

Configuration:

• Start with simple adapter scripts
• Test incrementally
• Use descriptive variable names
• CRITICAL: Never output raw analog values in data-items
  • Create intermediate variable for logic (e.g., ct-voltage-int)
  • Create cleaned variable with resample and min-delta for output
  • Only output cleaned variables to reduce noise and database load
• Reference: Adapter Scripts Introduction
• Keep backup of working configurations

Part Counting:

• Prefer dedicated part count relay
• Use pallet changer signal when available
• Use barfeeder pulse when applicable
• Coolant pulse method is last resort only

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