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Safety > Trapped Key Interlock Switches > Solenoid Locking Trapped Key Switches

Dold Solenoid Locking Trapped Key Interlock Switches

Trapped key systems use a series of mechanical locks and keys to control the access of gates or doors to running equipment or machines, ensuring safe access. Solenoid locking gate sets, available with one to five gate switch modules, afford maximum protection by adding electrical interlocking, and can be configured in series or parallel arrangements.

Standard Trapped Key Switches

Solenoid Locking Trapped Key Switches

Trapped Key Accessories

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Trapped Key Safety Interlock Switches

Series of Mechanical Locks and Trapped Keys to Ensure Safety

Trapped Key Interlock System
Solenoid Trapped Key Interlock System
Trapped Key Accessories
Actuator Keys
Mounting Plates

Trapped Key System

A trapped key system uses a series of mechanical locks and keys to control the access of gates or doors to running equipment or machines, ensuring safe access to those machines.

Systems are set up in a predefined sequence, preventing accidental access to running equipment.
An operator must shut down machinery and lock it down, then remove the key and use the same key to unlock the door or doors that access the machinery.
Keys are trapped and released in a sequential order:

The main station has a switch module and optional solenoid actuator;
Door stations have mechanical, rather than electrical, systems to provide safety for one or a series of gates;
This system allows the control of a series of lock points;
Human operation of locking/unlocking provides first hand, observable safety.

The trapped key system is cost-effective for multiple locks over a large area and eliminates the cost of running electrical wiring over long distances.
Note: Ordering a larger gate set than needed for the number of gates in a system compromises the safety integrity of that system. Spare keys are not available.

Selecting a Dold Trapped Key Gate Set

Watch the Videos - Trapped Key Interlock Safety Systems

Investing in Safety

Trapped Key Overview

Trapped Key Hints

Trapped Key Interlock System - SX and ZRH Series

Dold Safemaster Trapped Key System Gate Sets provide a full trapped key safety system, in one- to five-gate sets. They are available in either standard (SX) or solenoid-locking (ZRH) versions. All keys and their corresponding 01 and 10 modules are identical within a set, but unique to any other set. Also available are tongue key actuators (purchased separately from the gate sets), and optional items such as door actuators, captive safety key sets, key modules for key exchange box setup, and mounting plates.

Easy installation through comprehensive accessories
Mechanical safeguarding
One- to five-gate sets available
Solenoid and standard versions available
One conduit opening that accepts M20 x 1.5 fittings
316L stainless steel interlock safety switch body, coded trap key modules, coded keys, and tongue (key) gate actuator modules
For safety applications up to PLe/Category 4 according to EN/ISO 13849-1
Order actuating tongue (key) separately

Standard Gate Sets (SX)

316L stainless steel body interlock safety switches
(1) NC and (2) forced opening NO / NC changeover contacts

Solenoid Gate Sets (ZRH)

Interlocking safety switch with solenoid (24 VAC/DC), power to unlock
(1) NC and (2) forced opening NO and NC changeover contacts for actuator tongue (key) status, (2) NC and (1) forced opening NO and NC changeover contacts for solenoid status

Standard (SX) versions start at
$846.00
(SX-1GATE-SET)

Solenoid (ZRH) versions start at
$1,030.00
(ZRH-1GATE-SET)

Dold Trapped Key System Overview

Trapped Key Accessories

The following optional actuator key sets can be used with any of the Safemaster trapped key gate sets:

1001-KEYMODULE-SET modifies an SX-GATE-SET or a ZRH-GATE-SET to implement a key exchange box. Uniquely keyed within itself, this set allows for expansion of a key exchange plan.
PADLOCKMODULE-SET adds a personal safety feature for protection against being locked into a gate. One or more personal padlocks can be applied to the module. While a padlock is fixed to the module, the system cannot be restarted.
ACTUATOR-SET-B is a gate actuator. It can be added anywhere a gate function is required, so that the SX or ZRH module can be used to protect or to lock a gate.
01-SAFETY-KEY-SET adds a personal safety key as protection against being locked into any module of an SX or ZRH gate set. This key is normally trapped; when released the operator can take it while in the machine.

Trapped key accessories start at
$141.00
(ACTUATOR-SET-B)

Trapped Key Accessories Overview

Tongue Interlock Safety Switches and Keys

Trapped Key Actuators

Trapped key gate sets require one or more tongue key actuators.

ST2311-C-ACTUATOR
4-spring actuator, 316L stainless steel, 90� flexible mounting tab
ST2312-CS-ACTUATOR
Sliding actuator with spring, 316L stainless steel, flexible handle
ST2317-T-ACTUATOR ... New!
Standard right angle actuator, 316L stainless steel, 90� mounting tab

Tongue key actuators start at
$12.50
(ST2317-T-ACTUATOR)

Trapped Key Tongue Actuators Overview

Trapped Key Mounting Plates

Mounting plate size depends on size and number of modules in the application.

316 Stainless steel plates are sized to easily mount various configured trapped key stations
8 pre-fabricated sizes

Trapped key mounting plates start at
$38.00
(ST2361100-PLATE-2)

Trapped Key Mounting Plates Overview

Warning: Machine safety products sold by AutomationDirect are safety components only.

The purchaser/installer is solely responsible for the application of these components and ensuring all necessary steps have been taken to assure each application and use meets all performance and applicable safety requirements and/or local, national and/or international safety codes as required by the application. AutomationDirect cannot certify that our products used solely or in conjunction with other AutomationDirect or other vendors products will assure safety for any application.

Any person using or applying any products sold by AutomationDirect is responsible for learning the safety requirements for their individual application and applying them, and therefore assumes all risks, and accepts full and complete responsibility for the and suitability of the product for their respective application.

AutomationDirect does not provide design or consulting services, and cannot advise whether any specific application or use of our products would ensure compliance with the safety requirements for any application.

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Trapped Key Safety Interlock Switches

Series of Mechanical Locks and Trapped Keys to Ensure Safety

Trapped Key System

Watch the Videos - Trapped Key Interlock Safety Systems

Trapped Key Interlock System - SX and ZRH Series

Standard Gate Sets (SX)

Solenoid Gate Sets (ZRH)

Trapped Key Accessories

Trapped Key Actuators

Trapped Key Mounting Plates

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