How could i connect a week clock from the panel but not from the external pushbuttom

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DIRECT ANSWER TO THE QUESTION - Wire the week clock’s volt‑free dry NO contact directly at the controller terminals inside the panel, across the same COM and STARTOPEN input that the external pushbutton uses. Do not route through or from the external pushbutton station. - If your controller offers separate OPEN and CLOSE or HOLD‑OPEN inputs, use two timer outputs or an interposing relay pair so the timer can issue distinct openclose commands from the panel without touching the external pushbutton wiring. KEY POINTS - Use dry contacts from the week clock; do not switch the controller’s mains supply with the timer. - Land the timer wires on the control board terminals COM + STARTOPEN, and optionally COM + CLOSEHOLD‑OPEN. - Add an interposing relay if the timer does not provide clean dry contacts or if voltage levels differ. - Program the timer to output short pulses about 0.5–2 s unless using a maintained HOLD‑OPEN input. DETAILED PROBLEM ANALYSIS - Objective: Automate a gatedoor via a week clock “from the panel,” independently of any wall or post‑mounted pushbutton. Electrically, the pushbutton is just a momentary dry contact across the controller’s command input. The cleanest way is to land the timer’s dry contact directly on the same controller input terminals inside the control panel. This keeps external pushbutton wiring untouched yet allows either device to command the controller. - Inputs on typical controllers e.g., Crawford ECS950 with CDM9 include: - STEPSTART aka “step‑by‑step” or “impulse”: each pulse toggles open–stop–close. - OPEN and CLOSE: dedicated one‑way commands. - HOLD‑OPEN or KEY: maintained input to keep the doorgate open while active. - Strategies: 1 Single‑input strategy most common: Parallel the timer’s NO contact with the START input at the panel. The timer issues a brief pulse at desired times, exactly like a pushbutton press. External pushbuttons remain fully independent. 2 Two‑input strategy more deterministic: Use two separate timer channels or a DP relay module so you can drive OPEN at morning time and CLOSE in the evening using distinct inputs. This avoids step‑sequence ambiguity and prevents an unintended close if the door was already moving. 3 HOLD‑OPEN strategy: If you want a site to remain open during business hours, program the timer to assert a maintained contact onto HOLD‑OPEN between, say, 07:00–19:00. The controller opens, stays open, and then closes when the input releases assuming auto‑close is configured or you pulse CLOSE. - Why not switch the controller’s mains with the timer? Power‑cycling a control panel to “automate” it is poor practice: you lose self‑learning limitslogs, delay startup, and risk faults. Always command via the low‑voltage inputs with dry contacts. CURRENT INFORMATION AND TRENDS - Most industrial gatedoor controls including ECS family with CDM controllers expect dry‑contact commands on low‑voltage terminals. Many panels provide 24 V ACDC auxiliary power for accessories; time switches increasingly support universal supplies e.g., 24–240 V ACDC and multiple channels for clean openclose scheduling. - Best practice is moving from single step inputs to dedicated OPENCLOSEHOLD‑OPEN logic or to small logic relays for deterministic schedules and safety interlocks. SUPPORTING EXPLANATIONS AND DETAILS - Electrical interface: - Dry contact = a relay contact that does not source voltage. It simply connects two controller terminals together e.g., COM and START. - Interposing relay: If your timer only sources voltage e.g., 230 V output or you want extra isolation, drive a DIN‑rail relay coil with the timer; use the relay’s NO dry contact on the controller input. - Pulse timing: - START input typically needs a momentary closure; 0.5–2 s is standard. - HOLD‑OPEN requires a maintained closure for the whole interval. - Protection: - Coil suppression flyback diode for DC coils or RC snubber for AC coils prolongs contact life and reduces EMI. - Separate the low‑voltage control wiring from mains wiring inside the panel; use ferrules and label everything. ETHICAL AND LEGAL ASPECTS - Safety: Unattended motion introduces entrapment hazards. In the US, UL 325 and ASTM F2200 require functional entrapment protection photo eyesedges during automatic close. Do not bypass safety inputs. Test safety devices after changes. - Access control: Ensure the schedule does not compromise site security; coordinate with stakeholders and post signage about automatic operation. - Compliance: Follow local electrical codes e.g., NEC, use listed components, and maintain clear labeling and documentation. PRACTICAL GUIDELINES - Step‑by‑step wiring generic, panel side only: - Identify controller terminals: - COM common0 V for inputs - START or STEP input for single‑button behavior - Optional OPEN, CLOSE, HOLD‑OPEN inputs - Auxiliary power often 24 V ACDC if you will power the timer from the panel - Power the week clock: - If it accepts 24 V from the panel, use the aux supply with a small in‑line fuse or breaker. - If it requires 120230 V, feed it from a protected branch inside the panel with segregation from ELV wiring. - Connect control contacts: - Single‑input: Timer NO contact to START; the other side to COM. - Dual‑input: Use two timer relays: NO1 to OPEN–COM; NO2 to CLOSE–COM. - HOLD‑OPEN: Timer NO to HOLD‑OPEN–COM; program a maintained interval. - Commissioning: - Program datetime and events. For START, use short pulses. For HOLD‑OPEN, use maintained periods. - Verify each scheduled event while observing safety sensors. - Confirm that manual pushbuttons still work; they are electrically independent. - Recommended add‑ons: - DIN rail interposing relays with LED indication. - Override selector AUTO–MANUAL to disable the timer during maintenance. - Surge protection if in noisy industrial environments. POTENTIAL CHALLENGES AND HOW TO OVERCOME THEM - Ambiguous motion with STEP input: Use OPENCLOSE inputs or HOLD‑OPEN to avoid state ambiguity. - Timer lacks dry contacts: Add an interposing relay rated for the controller’s ELV input. - Electrical noise causing false triggers: Use shielded cable for long runs, proper grounding, and input debounce some controllers allow configurable input filters. - Mixed voltages inside the panel: Keep segregation and use proper barriersducting to maintain creepageclearance. POSSIBLE DISCLAIMERS OR ADDITIONAL NOTES - Terminal names differ between models; always verify against your controller’s manual before wiring. - Do not exceed input currentvoltage ratings; controller inputs are typically ELV logic expecting dry contacts. - If your site requires unattended closing, ensure redundant entrapment protection and periodic test logs. SUGGESTIONS FOR FURTHER RESEARCH - Obtain the exact installationwiring manual for your control panel to confirm terminal identifiers and input behaviors. - If you require advanced schedules holidays, astro, consider a two‑channel DIN‑rail astro time switch with programmable pulse widths. - For complex logic e.g., inhibit closing if photo eye failed, a small logic relay e.g., programmable relay between timer and controller can implement safe interlocks. BRIEF SUMMARY - Connect the week clock inside the panel directly to the controller’s low‑voltage command inputs using dry contacts—parallel to START for simple automation, or to dedicated OPENCLOSEHOLD‑OPEN inputs for deterministic behavior. Power the timer appropriately, use interposing relays where needed, keep safety circuits intact, and avoid switching the controller’s mains supply with the timer. If you share your exact controller model and the timer model and whether it has one or two relay outputs and what power it needs, I can give you a terminal‑by‑terminal wiring sketch and a recommended event program.

Wiring a Week Clock Timer Directly to Gate Controller Panel (e.g., Crawford ECS950, CDM9) Without Using External Pushbutton

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