Skill: Safety Edge Interface Wired (e.g. CCE 4ch)
Skill level: 3
Wiring
Learning Objective:
Learn how to correctly wire and configure a CCE wired 8k2 edge interface, power it safely, manage multiple edges on one channel, test function, and simplify relay output wiring — while ensuring clarity and future-proofing.
1. Overview
8k2 Wired Edge Interfaces (such as the CCE 4ch) are used to connect resistive safety edges to gate control systems. They convert the variable resistance of the safety edge into a simple relay output that the control board can understand.
8k2 refers to 8,200 Ohms – the resistance measured across a safety edge when it is not activated.
When the edge is activated (pressed), the resistance drops to under 100 Ohms, almost a short circuit.
This design adds an important layer of safety: the control board can continuously check that the safety edge circuit is intact and ready to respond.
Most control boards will only accept 1 or 2 wired 8k2 edges directly, but a typical gate system may require 5–7 edges. An 8k2 interface solves this by allowing multiple edges to be connected while still presenting a clean, reliable signal to the control board.
If a safety edge is activated or becomes faulty, the interface output goes open circuit, signalling the control board to immediately stop gate movement.
A CCE wired edge card:
Runs on 24V AC or DC supply.
Accepts up to 2 safety edges per channel.
Provides relay outputs (COM/NC) for board connection.
Internal jumpers allow configuration for 1 edge (8k2) or 2 edges (4k1).
⚠️ Incorrect jumper setting will cause constant fault or non-detection.
⚠️ Never attempt to connect more than 2 edges per channel.
2. Tools and Materials Required
Multimeter (Ohms + continuity)
Screwdrivers and wire strippers
Edge interface (e.g. CCE 4ch)
Spare 8k2 resistors (from kit)
Cable markers and zip ties
Silicone or mounting pegs
Labels or cable IDs
3. Before You Start
Confirm voltage type and rating from the interface label/manual (24V AC/DC).
Standard colour convention:
Red = +24V
Blue = 0V (–/GND)Verify supply voltage at terminal with meter before connection.
Identify intended edge wiring (brown/white typical), label incoming edges.
Decide jumper settings (8k2 for one edge, 4k1 for two edges).
4. Procedure
See diagrams and/or instruction manual in the following sections
4.A Power Supply
Connect Red = +24V, Blue = 0V.
Test supply voltage before connecting to ensure stability.
4.B Terminal Overview (CCE Example)
Starting at the power terminals: 1+2 power input.
3+4 Autotesting
5+6 relay outputs → RL2 n/c
7+8 relay outputs → RL1 n/c
9+10 Edge input 2 8k2
11+12 Edge input 1 8k2
4.C Jumper Settings
Edge 1 input → Jumper P3. 1 edge = on, 2 edges = off
Edge 2 input → Jumper P4. 1 edge = on, 2 edges = off
Do not exceed 2 edges per channel.
Label jumper setting on enclosure lid for clarity.
4.D Relay Output Wiring
Option 1: Connect RL1 and RL2 separately to board.
Option 2: Series wiring for combined output (saves cable, as per wiring diagram below):
RL1 COM → supply/common (Black).
RL1 NC → RL2 COM.
RL2 NC → board input (Yellow).This breaks safety circuit if any connected edge activates.
4.E Testing and Function
Optionally use a spare 8k2 resistor to simulate an edge.
Check LED indicators:
Green = normal.
Red = edge activated or fault.Press edge → LED red, relay clicks.
Measure resistance:
8.2kΩ = single edge.
4.1kΩ = doubled edges.
Open/0Ω = fault.
4.F Mounting and Finishing
Mount securely on board pegs with M4 thread (don't use sticky feet, they fall off)
Do not leave loose inside enclosure.
Seal and label wiring:
Red/Blue = Power.
Brown/White = Edge.
Black/Yellow = Relay output.Photograph wiring and jumper positions for Clik/AppSheet.
5. Best Practices
✅ Use standard colours (Red/Blue for power, Brown/White for edges).
✅ Clearly label edges for fault diagnosis later.
✅ Wire relay outputs in series if you need to save cable runs.
✅ Always test edge press with LED and meter before handover.
✅ Securely mount interface, never leave it loose in housing.
✅ Photograph and log wiring and settings in Clik.
6. Common Mistakes to Avoid
🚫 Misconfiguring jumpers → permanent fault light or no detection.
🚫 Trying to connect 3+ edges per channel → unreliable detection.
🚫 Forgetting to check voltage before wiring → damage to interface.
🚫 Leaving interface loose in enclosure → risk of shorts or vibration damage.
🚫 Not labelling or photographing → confusion for future engineers.
7. Safety Information
Relevant SSOW References:
SSOW-01: Electrical Isolation & Lock-off
SSOW-03: Safe Low Voltage Wiring (ELV <50V DC)
SSOW-05: Safe Use of Multimeters
SSOW-09: Manual Handling (control panels, housings)
SSOW-11: PPE (gloves, boots, eye protection)
⚠️ Always test voltage with a meter before powering interface.
⚠️ Do not exceed 2 edges per channel — split across channels if required.
⚠️ Ensure interface is mounted securely and wiring is insulated.
2 edges
4 edges
