Siemens 3TX4001-2A Auxiliary Contact Block

This legacy Siemens SIRIUS front-mounted auxiliary contact features 1 通常閉 (ノースカロライナ州) 接触, compatible with 3TF3 / 3TF4 contactors. Original production discontinued on Oct 01, 2021 with no identical OEM replacement. Recommended drop-in alternative: domestic compatible 3TY7561-1AA00, or upgrade to 3RH2911-1AA01 for 3RT6 series contactors.

1. モデルコードの内訳

2. Core Electrical Specifications

3. Full Same-housing Model List (3TX4 Series)

4. Full Compatible Contactor List (Exclusive for Front Snap Fit)

Only applicable to below 3TF series, incompatible with newer 3RT / 3RV ranges:

3TF30: 3TF3000~3TF3090 (9A~12A)

3TF31: 3TF3100~3TF3190 (12A~16A)

3TF32: 3TF3200~3TF3290 (16A~25A)

3TF33: 3TF3300~3TF3390 (25A~32A)

3TF34: 3TF3400~3TF3490 (32A~40A)

3TF40~45: 3TF4000~3TF4590 (40A～95A)

> 注記: One contactor can mount 1 front block + 2 side auxiliary blocks simultaneously, max expansion up to 6 補助接点 (3NO +3NC).

5. Replacement Selection Guide for Obsolete Item

5.1 Direct Drop-in Replacement (No Contactor Modification)

5.2 Full Unit Upgrade (3TF → 3RT6)

6. アプリケーション環境 & Industrial Cases

✅ Approved Application Scenarios

1. Motor Control Circuits: Fault feedback & star-delta interlock for 3TF contactors of fans & ウォーターポンプ
2. PLC Interface: NC contact feeds contactor open/closed status into PLC digital input modules
3. Safety Interlock: 非常停止 & access door protection; NC forced opening cuts control supply (EN準拠 60204-1)
4. ステータス表示: Pilot lamp power switching; NC opens to turn off indicator when contactor energizes

❌ Forbidden Applications

1. Direct main-circuit loading: Designed exclusively for control loops (coils, pilot lamps, PLC signals); never connect to power main circuit
2. Harsh ambient: 避ける >60℃, 重い粉塵, corrosive chemical & non-enclosed cabinets (accelerates contact oxidation)
3. High-frequency cycling: >10 サイクル/分; use solid-state relays instead
4. DC heavy-load circuits: AC-15 rating invalid for DC-13 duty; select dedicated DC auxiliary contacts

産業応用事例

7. 一般的な障害のトラブルシューティング

8. Quick Selection Mnemonic

4001 =NC, 4010 = NO; front snap exclusively for 3TF;<br>Obsolete → swap to 3TY; upgrade to 3RT with 3RH;<br>Only for control circuit, never main power, excellent for safety interlock!

9. HSコード & 航空輸送のコンプライアンス

HSコード: 85365000 (Electrical switching apparatus for circuit protection)

Air Transport Classification: 非危険物, purely mechanical contacts with no lithium battery/supercapacitor, compliant with IATA DGR

CE認証: Complies with Low Voltage Directive 2014/35/EU; Certificate of Conformity available upon request

Application Scope of 3TX4001-2A (Front-mounted 1NC Auxiliary Contact)

Product Feature: Snap-on external 1NC contact for 3TF3/3TF4 contactors, rated AC-15, dedicated for secondary control circuit only, NOT permitted in main power circuit.

1. Standard Common Applications

1.1 Motor Start-Stop Control (ファン, Water Pumps, エアコンプレッサー)

1. Passive running status feedback

Contactor coil energizes → NC opens, sends closing/running feedback signal to PLC DI module; coil de-energizes → NC resets closed to transmit stop signal.

Typical usage: Chilled water pumps, cooling blowers, 循環ポンプ, central air-conditioning units.

2. Electrical interlock protection

Mutual NC interlock between two contactors (forward/reverse or star-delta) to avoid simultaneous closing and phase short-circuit.

例: Star-delta motor starter interlock between star & delta contactors.

1.2 工作機械 & Automation Equipment (Lathe, Conveyor, Injection Molding Machine)

1. Cabinet door interlock: NC of main contactor wired into safety loop; if contactor is welded closed, NC stays open to block equipment restart.
2. Conveyor sequential interlock: Interlock between upstream & downstream conveyor contactors to prevent mechanical collision from misoperation.
3. 故障警報: Normally closed NC in series with fault indicator lamp; lamp lights at standby/shutdown and goes off when contactor pulls in.

1.3 HVAC Industry (Central AC, Fresh Air Unit, Smoke Exhaust Fan)

1. BA system signal collection: Fan contactor NC feeds start/stop remote data to building management controller.
2. Fire smoke exhaust interlock: NC links with fire damper; damper shutdown cuts fan control circuit.

1.4 Water Treatment Equipment (Dosing Pump, Sewage Pump, Aeration Blower)

1. Pump overload linkage: Thermal relay trip resets contactor, closed NC triggers audible-visual fault alarm.
2. Duty/standby pump auto-switch: Main pump fault closes NC to activate backup pump automatically.

1.5 LV Power Distribution Panels

1. Capacitor compensation cabinet: NC of switching contactor feeds capacitor switching status to reactive power regulator.
2. ATS cabinet: Electrical interlock between normal & backup supply contactors to eliminate cross-source short-circuit risk.

1.6 Hoisting & Elevator Auxiliary Control

Brake contactor NC of overhead crane feeds brake open/closed feedback; also for cooling fan contactor status monitoring on elevators.

2. Safety Circuit Exclusive Usage (Positively Driven Contact per Machinery Safety Standards)
3. Emergency stop monitoring: Detects welded contactor fault; mechanically stuck contactor keeps NC open to lock control power off.
4. Safety guard circuit: Equipment door opening de-energizes main contactor, closed NC locks startup circuit.
5. Low-power Indicator & Small Relay Driving
6. Standby pilot lamp: NC closed to light indicator at idle; NC opens to turn lamp off during equipment operation.
7. Mini intermediate relay drive: NC switching controls relay coil to amplify load capacity.
8. Prohibited Application List
9. ❌ Never connect to 220V/380V main power loop; AC-15 rating only for control loads, cannot directly drive motor/heater high-power loads.
10. ❌ Avoid >55℃, strong acid/alkali corrosion & unprotected open-air cabinets (accelerates contact oxidation & bad conduction).
11. ❌ Unsuitable for heavy DC loads (no DC-13 rating; DC breaking easily causes arc burnout).
12. ❌ Ban over 15 switching cycles per minute (fast mechanical wear; replace with solid-state relay).