Safety relay

PNOZsigma

Panel width is a real constraint, and PNOZsigma is designed around it. The manufacturer positions the family as delivering maximum functionality in minimum width, with push-in spring terminals and a consistent terminal layout across device versions that keeps installation and later fault-finding straightforward.

E-STOP, gate, light barrier, two-handNarrow housing widthsPush-in spring terminalsSelectable operating modesUp to PL e / SIL CL 3
PL eUp to, device dependent
SIL CL 3Up to, device dependent
5000 mAltitude on numerous devices
Pilz PNOZ safety relay family including PNOZsigma narrow-width devices
PNOZsigmaFamily range shown; device selected from the safety function
PL eUp to, per device
SIL CL 3Up to, per device
20%Wiring reduction via expansion connectors
5000 mAltitude on numerous devices
Why it is specified

PNOZsigma is built around

The design choices target installation time and panel space, which is where the cost usually sits on a series-built machine.

Function in minimum width

Diverse functionality packed into each device, in particularly narrow housing widths.

Rapid installation

Push-in spring terminals remove screw termination from the build.

Consistent terminal layout

Designation and position of the terminals is the same on all device versions, so connections can be assigned quickly during configuration, installation and diagnostics.

Wiring reduced by 20%

The manufacturer states wiring work is reduced by 20% where connectors are used to expand contacts.

Applications

PNOZsigma is used

The manufacturer lists safe monitoring of E-STOP, safety gates, light barriers, two-hand control devices and time, plus special applications including speed monitoring and safe brake control.

Emergency stop and safety door monitoring on industrial machinery
Stop and guard

E-STOP and safety gates

The core pairing on most machines: a monitored stop command and a guard position, evaluated with a defined reset behaviour.

ConfirmConfirm input devices, contacts and reset type.
Diagram of Pilz PNOZsigma safety relay features and benefits
Protective devices

Light barriers and two-hand control

Evaluation of electro-sensitive protective equipment and two-hand control devices where the operator works at the hazard.

ConfirmConfirm device type and output arrangement.
Safe speed monitoring on a machine drive using Pilz devices
Special functions

Speed and brake applications

The manufacturer lists speed monitoring and safe brake control among the special applications available within the range.

ConfirmConfirm which special function is required.
Technical data

Selection parameters that matter

These are the values that decide the device. Contact configuration, timing and supply vary across the family and belong to the selected order number.

Performance level and integrity level are device dependent. The manufacturer lists both PL e / SIL CL 3 and PL c / SIL CL 1 routes within the family.
Monitored functionsE-STOP, safety gates, light barriers, two-hand control devices and time
Special applicationsSpeed monitoring and safe brake control are available within the range
Performance levelUp to PL e; devices for PL c applications are also listed
Integrity levelUp to SIL CL 3; devices for SIL CL 1 applications are also listed
TerminalsPush-in spring terminals for rapid installation
Terminal layoutDesignation and position identical on all device versions
Contact expansionConnectors used to expand contacts; The manufacturer states wiring work reduced by 20%
Operating modesSelectable operating modes and timer functions
AltitudeNumerous devices suitable for use at heights up to 5000 metres
A device rated for PL e does not make a machine PL e. The achievable level follows from the complete safety function including the input device, the evaluation, the output stage and the machine response.
Models

Device selection within the family

The family is broad. These are the axes along which a specific device is chosen.

Function

Monitored safety function

The primary selection axis — which function the device must evaluate, and how many channels it takes.

Examples
E-STOP, gate
Also
Two-hand, time
Integrity

PL and SIL route

Devices are available for both the higher and the lower integrity routes; the requirement comes from the risk assessment.

Upper
PL e / SIL CL 3
Lower
PL c / SIL CL 1
Outputs

Contact configuration

Contact type and count vary; expansion connectors add contacts without full re-wiring.

Expansion
Connector-based
Wiring
−20% stated
Special

Speed and brake variants

Where the application needs speed monitoring or safe brake control rather than a stop function.

Speed
PNOZ s30
Brake
PNOZ s50
Accessories

Configuration, expansion and pairing

Most PNOZsigma projects involve a terminal choice, possibly a contact expansion, and the stopping element behind it.

Expansion

Contact expansion modules

Connectors used to expand contacts reduce wiring work; the expansion device is selected with the base relay.

ConfirmConfirm required contact count and load.
Configuration

PNOZsigma Configurator

Used for the configurable devices in the range, including the speed monitor, for parameter entry and diagnostics.

ConfirmConfirm whether a configurable device is involved.
Output stage

Contactors and feedback loop

The relay commands the stopping element; feedback loop monitoring of the contactors is part of the function.

ConfirmConfirm the stopping element and feedback arrangement.
Before quotation

Application review

A safety relay cannot be selected from a device name. These inputs determine the device, its contacts and its reset behaviour.

Safety function

  • Which function must be evaluated, and how many
  • Single or dual channel input, and cross-fault detection
  • Required performance or integrity level, if determined
  • Whether a special function such as speed or brake control is needed

Input devices

  • Type of input device and its contact or output arrangement
  • Whether devices are connected in series and the fault-detection effect
  • Cable lengths and connection method
  • Existing devices being retained

Outputs

  • Contact type, number of contacts and switching load
  • Stopping element — contactors, drive input, valve or brake
  • Whether feedback loop monitoring is required
  • Required stop category

Panel and operation

  • Available panel width
  • Supply voltage and terminal preference
  • Manual, monitored or automatic reset, and its position
  • Installation altitude if above normal ranges
Related technologies

PNOZsigma sits in the architecture

The relay is the evaluation stage between the input device and the stopping element. When functions multiply and begin to interact, a configurable controller usually becomes easier to maintain.

Guard switches and E-STOP devices
Light curtains and area protection
PNOZ s30 for speed and standstill
PNOZ s50 for safe brake control
myPNOZ for several linked functions
PNOZmulti 2 as function count grows
Diagram of Pilz PNOZsigma safety relay features