Wieland SNA-4053-K-A Safety Relay

SNA: Safety switch monitoring series (for monitoring emergency stop, защитные ворота, световые завесы безопасности)

4053: Код спецификации

К: Pluggable screw terminals

А: Supply voltage AC/DC 24 В

Suffix differentiation for the series:

A = AC/DC 24 В; C = Push-in spring terminals; KM = Automatic reset; KE = Special version

2. Основные характеристики & Рейтинги безопасности
3. Сертификаты безопасности

ПЛ е / Категория 4 (В ИСО 13849-1)

SIL CL3 (В 62061)

2. Конфигурация контактов

3 safety normally open contacts (13-14 / 23-24 / 33-34)

1 normally closed signal contact (41-42)

3. Электрические данные

Поставлять: 24 В переменного/постоянного тока

Continuous rated current Ith: 8 А

АС-15: 230 В / 5 А; DC-13: 24 В / 5 А

Монтаж: ОТ 35 мм рельс; Ширина 22.5 мм

4. Input Functions

Dual-channel safety circuit (S11/S12, S21/S22)

Supports cross-channel short-circuit monitoring

Ручной сброс (with reset monitoring)

Подходит для: Кнопки аварийной остановки, safety gate switches, magnetic safety switches, световые завесы безопасности

3. Typical Wiring Logic
4. А1(+), А2(-): 24 В источник питания
5. S11-S12, С21-С22: Dual-channel safety devices (normally closed signal)
6. S33-S34: Reset terminals (connect external normally open reset button; shorted = automatic reset)
7. 13-14 / 23-24 / 33-34: Safety outputs (for controlling main contactors)
8. 41-42: Normally closed fault feedback signal
9. Model Correction & Alternative Reference

⚠️ The most frequently confused model on the market: SNA4043K-A (4043, easily mistaken for 4053)

⚠️ Important Verification Conclusion

SNA4053K-A is NOT an official standard model in Wieland catalogues, it is highly likely a transcription error:

1. Most common miswriting: SNA4043K-A (Номер детали. R1.188.1810.0)

Автоматический сброс, no reset monitoring; dual-channel with short-circuit monitoring

2. Alternative similar model: SNA4063K-A

Ручной сброс (with reset monitoring) — this is the core difference from SNA4043

Model rules:

SNA4043K-A: Автоматический сброс

SNA4063K-A: Ручной сброс (reset button monitoring)

Both models share identical contact configuration, safety rating and dimensions; only reset logic differs.

Quick Selection Comparison Table

Recommended Actions

1. Verify the printed model on the physical nameplate of the unit;
2. Confirm site requirements: Reset monitoring required or not

Emergency stop circuits generally require manual reset (SNA4063K-A)

Safety light curtain applications may adopt automatic reset (SNA4043K-A)

Application Scenarios of Wieland SNA Series Реле безопасности (SNA4043 / SNA4063)

This series achieves PL e / Кат.4 / SIL3 with dual-channel monitoring, primarily deployed for safety circuits on machine tools and automated production lines. Content is divided into supported safety signal types, industry applications, and key selection differentiation.

1. Supported Safety Input Signals (Hardware Utilization)
2. Кнопки аварийной остановки (dual normally closed contacts)

Most common application: Machine main emergency stop and zone emergency stop circuits.

Standard requirement: Emergency stop circuits prefer SNA4063K-A (manual reset with monitoring).

2. Safety gate switches / Magnetic safety sensors

Interlock for protective doors, maintenance doors and perimeter fencing; power circuit cutout upon door opening.

3. Световые завесы безопасности

Hazard zone intrusion protection for presses, conveyor lines and robot stations.

Light curtain solutions commonly use SNA4043K-A (автоматический сброс).

4. Two-hand control devices

For stamping and riveting equipment, preventing single-hand access to hazardous zones.

5. Safety mats, safety bumpers

Perimeter intrusion detection around robot cells, automatic doors and lifting platforms.

2. Major Industry & Equipment Applications

(1) Станкостроительная промышленность

токарные станки с ЧПУ, machining centres, шлифовальные машины, punching machines, bending machines

Приложение: Protective door interlock, emergency stop circuits, safety light curtain protection

(2) Automated Production & Packaging Equipment

Упаковочные машины, palletizers, конвейерные линии, сортировочное оборудование, labellers

Robot workstations, gantry robot safety fence interlock

(3) Резина & Пластмассовая промышленность

Injection moulding machines, экструдеры, blow moulding equipment: Safety gates, аварийная остановка, световые завесы безопасности

(4) Логистика & Складское оборудование

Automated warehouses, lifts, shuttles, sorting lines

Подъемные платформы, dock leveller safety interlocks

(5) Новая Энергия & Оборудование для литиевых батарей

Cell assembly machines, electrolyte filling machines, sealing equipment, test tooling

Wieland products are widely adopted on export machinery to meet EU CE Machinery Directive requirements

(6) Woodworking & Печатное оборудование

Panel saws, режущие машины, printing presses, die-cutting machine safety protection

(7) General Custom Automation

Custom test fixtures and assembly machines; deployed as core safety logic unit to cut off main contactors and servo power circuits.

3. Critical Application Selection Comparison

⚠️ SNA-4053-K-A is not an official Wieland standard model. It is almost certainly a nameplate transcription error; physical unit will be one of the two above variants.

4. Ограничения & Unsuitable Applications
5. Cannot directly drive high-power loads; safety contacts are intended to control contactor coils, not motors directly
6. Not suitable for solenoid valves or high-frequency switching loads
7. Cannot satisfy safety requirements higher than PL e / Кат.4 (this series already reaches Cat.4 maximum rating)

Selection Guidelines for Wieland SNA / SNO Safety Relays

Based on the SNA4043 / SNA4063 platform covered above; structured criteria ready for engineering proposals and procurement checks.

Шаг 1: Confirm Required Safety Rating (Mandatory Priority)

Соответствует ISO 13849-1 / В 62061

1. PL & Категория

ПЛ е / Кат.4: Highest rating. For high-risk stations including robots, stamping, injection moulding, machine tools and lithium battery equipment (supported by all mainstream SNA variants)

PL d / Cat.3: Low-risk general automation and conveyor lines

2. SIL Level

СИЛ 3 corresponds to PL e; preferred for machinery exported to EU

✅ Selection Rule: Do NOT downgrade safety rating for high-risk equipment.

Шаг 2: Determine Safety Input Channel Configuration (Dual Channel Is Standard)

Channel Modes

Dual-channel monitoring with cross short-circuit detection: Industry standard, fitted across all SNA variants. Compatible with dual normally closed safety devices (Аварийный останов, защитные ворота, легкие шторы)

Single channel: Only permitted for low-risk scenarios; available on selected SNO variants. NOT allowed for high-risk machinery.

Compatible Sensor Types

Emergency stop switches, mechanical safety gates: Dual normally closed (Северная Каролина)

Магнитные предохранительные выключатели, световые завесы безопасности: Двойной НЗ / OSSD signals

⚠️ Two types of safety light curtains:

① OSSD solid-state output → Requires relay model supporting OSSD input

② Light curtain with relay converted contact output → Compatible with standard SNA4043 / SNA4063

Шаг 3: Режим сброса (Most Common Source of Wrong Selection!)

Ключевое отличие:

Monitored reset detects open or short circuits on reset wiring and triggers safety lockout for superior safety. Simple unmonitored manual reset should be avoided on new projects.

Шаг 4: Напряжение питания

Main Wieland options:

Suffix A = AC/DC 24 В (Automation standard, selected in 90% of projects)

Less common: 110 ВАК, 230 VAC — only for legacy retrofits

Пример: SNA4063K-A → A = AC/DC 24 V supply

Шаг 5: Тип терминала (Identified by Suffix K / С)

K = Pluggable screw terminals

Преимущества: Vibration resistant, ideal for permanent cabinet installation and on-site maintenance (the unit in your photo uses K terminals)

C = Push-in spring terminals

Преимущества: Fast wiring without screwdrivers; use cautiously under heavy vibration

Пример: SNA4063K-A

Шаг 6: Output Contact Configuration

Main Safety Outputs (For Power Circuit Cutoff)

SNA4043 / SNA4063: 3 normally open safety contacts

Цель: Wired in series with main contactor coils for redundant shutdown

Auxiliary Signal Contacts (PLC Feedback)

1 built-in normally closed fault contact

Opens upon safety activation or relay fault; used for alarm indicators and PLC signalling

Selection Note: If multiple feedback signals are required, add auxiliary relays. Safety contacts should not be expanded externally.

Contact Load Ratings

АС-15: 230 В / 5 А

DC-13: 24 В / 5 А

👉 Never drive motors directly; only control contactor coils!

Шаг 7: Монтаж & Физические характеристики

1. Монтаж: Standard DIN 35 мм рельс
2. Ширина: SNA40xx series 22.5 мм, compact design saving cabinet space
3. Environmental rating: IP20 (for cabinet installation only; not for outdoor direct deployment)

Шаг 8: Differentiate SNA vs SNO Series (Frequent Confusion)

SNA Series: Dual-channel safety monitoring, up to PL e Cat.4; for emergency stop, защитные ворота, легкие шторы (your target series)

SNO Series: Predominantly single channel, lower safety rating generally PL d and below; low-cost basic solutions

Common Selection Pitfalls Checklist

1. ❌ Misapplication: Using automatic reset SNA4043 for emergency stop circuits — violates machinery safety standards, fails third-party audit & Сертификация CE
2. ❌ Transcription error SNA-4053-K-A: No official model; physical unit is either SNA4043 or SNA4063
3. ❌ Direct drive of solenoid valves or high-power loads with safety contacts → contact burnout and loss of safety function
4. ❌ Mixing K screw terminals and C spring terminals, leading to mismatch on delivery
5. ❌ Ignoring reset monitoring requirements → machine fails acceptance testing

Rapid Selection Workflow (For Field Engineers)

1. Identify safety device: Аварийная остановка / safety gate → select SNA4063xx-A (monitored manual reset); Light curtain / safety bumper → SNA4043xx-A (автоматический сброс)
2. Confirm supply voltage: Default AC/DC24V suffix A
3. Select terminal type: Permanent cabinet installation → K screw terminal; high volume assembly for fast wiring → C spring terminal
4. Verify safety rating: High-risk equipment requires PL e / Кат.4 / уровень безопасности SIL3
5. Confirm number of safety contacts sufficient for contactor control

Complete Official Model List of Wieland SNA40xx Safety Relays

Series Profile: safeRELAY SNA40xx dual-channel safety monitoring, ПЛ е / Кат.4 / уровень безопасности SIL3, Монтаж на DIN-рейку;

⚠️ Важное примечание: SNA-4053-K-A is NOT an official Wieland model, it is a transcription error. Official core variants are limited to 4043 / 4044 / 4063 / 4064;

Industry standard: Suffix A = AC/DC24 V (automation default). Specify A suffix for new orders.

1. Правила именования моделей

`SNA 40XX [Терминал][Перезагрузить]-[Voltage Suffix]`

1. SNA: Dual-channel safety monitoring base unit
2. 40ХХ:

4043: 3 safety NO contacts, автоматический сброс (no reset monitoring)

4044: 4 safety NO contacts, автоматический сброс (no reset monitoring)

4063: 3 safety NO contacts, ручной сброс (with reset circuit monitoring)

4064: 4 safety NO contacts, ручной сброс (with reset circuit monitoring)

Last digit 3 = 3 safety NO contacts; Last digit 4 = 4 safety NO contacts

3. Terminal Code

К: Pluggable screw terminals (most widely used in projects)

С: Pluggable Push-in spring terminals

4. Extended Reset Suffix (KM/KE)

км: Simple manual reset without monitoring; rarely specified for new projects

5. Voltage Suffix

А: переменный/постоянный ток 24 В (automation standard)

Нет суффикса: Fixed screw terminals (legacy models, прекращено)

2. Mainstream Models for Domestic Projects (24 В переменного/постоянного тока)

SNA4043 Series | Автоматический сброс, 3 Safety NO Contacts

SNA4044 Series | Автоматический сброс, 4 Safety NO Contacts

SNA4063 Series | Ручной сброс (Контролируемый), 3 Safety NO Contacts【Preferred for Complete Machinery】

SNA4064 Series | Ручной сброс (Контролируемый), 4 Safety NO Contacts

3. Legacy Non-Standard Voltage Models (Only For Equipment Replacement, Not Recommended For New Projects)

Fixed non-pluggable screw terminals (no suffix A)

SNA4043K: AC42~48 V / AC115 V / AC230 V

SNA4063K: AC230 V

Примечание: All new domestic machinery shall adopt AC/DC24 V models with suffix -A

4. General Specifications Applicable to All Variants
5. Рейтинг безопасности: ПЛ е / Кат.4, СИЛ 3 (ЭН ИСО13849-1, EN62061)
6. Contact Ratings: АС-15 230 V/5 A; DC-13 24 V/5 A
7. Монтаж: ОТ 35 мм рельс; Ширина 22.5 мм; IP20 (Cabinet installation only)
8. Функции: Dual-channel cross short-circuit monitoring, EDM external device monitoring support, 3 status LED indicators
9. Электропроводка: Supports single-channel / dual-channel connection modes
10. Quick Selection Summary Table

6. Procurement Reminders
7. If customer submits model `SNA-4053-K-A` → Confirm transcription error immediately. Check physical nameplate; the actual unit is almost certainly SNA4063K-A.
8. Always include complete model + manufacturer part number in BOM to avoid delivery mismatch between K screw terminals and C spring terminals.
9. Do not interchange automatic reset SNA4043 and monitored manual reset SNA4063; incorrect selection will lead to failed safety acceptance.
10. Contact count selection: 3 contactors or less → SNA4063; ≥4 contactors requiring synchronous shutdown → select SNA4064.