Phoenix Contact PSR-SCP-24DC/ESP4/2X1/1X2 Replacement

Product Overview

Phoenix Contact PSR-SCP-24DC/ESP4/2X1/1X2 2981020 Replacement & Upgrade Solution for PSR-SCP Series

Upgrading or replacing a safety relay in an operational control system demands zero compromise on compatibility. The Phoenix Contact PSR-SCP-24DC/ESP4/2X1/1X2 (Article No. 2981020) is a 24 VDC single-channel/two-channel safety relay module from the PSR-SCP Series, designed for emergency stop, safety gate, and light curtain monitoring applications. Whether you are replacing a failed unit, retiring an end-of-life safety circuit, or modernizing a legacy machine safety architecture, this module provides a direct, drop-in upgrade path with minimal rewiring and zero PLC program changes.

Many facilities running older PILZ PNOZ X-series relays, Schmersal SRB-series modules, or first-generation Phoenix Contact PSR-PC safety relays are now migrating to the PSR-SCP platform. The PSR-SCP-24DC/ESP4/2X1/1X2 maintains the same standard 22.5 mm DIN rail footprint as its predecessors, allowing direct substitution inside existing control cabinets without panel modification. The screw terminal layout follows the EN 60715 standard, and the input circuit accepts both NC contact chains and monitored reset signals, preserving compatibility with existing field wiring from E-stop buttons, rope-pull switches, and two-hand control stations.

For sites currently operating Phoenix Contact PSR-SCP-24DC/ESD/4X1/1X2 or PSR-SCP-24DC/ESAM4/3X1/1X2 variants, the migration to the ESP4 input configuration requires only a review of the monitored contact count — no new cable runs are needed in most retrofit scenarios. The relay output stage delivers two safety-rated N/O contacts (13-14, 23-24) and one auxiliary N/C contact (41-42), matching the output topology of the majority of PSR-SCP predecessors and enabling direct substitution in the downstream contactor or valve wiring without rewiring the load circuit.

Compatibility Comparison Table

Seamless Upgrade Solutions

A complete safety circuit migration rarely involves a single component. When replacing the PSR-SCP-24DC/ESP4/2X1/1X2, engineers typically review the entire safety loop for compatibility. The 24 VDC supply feeding the relay is commonly sourced from a Phoenix Contact QUINT-PS/1AC/24DC/10 or TRIO-PS/1AC/24DC/5 power supply module — both of which provide the stable, low-ripple 24 VDC rail that the PSR-SCP input circuit requires for reliable cross-circuit monitoring.

On the input side, field devices such as Schmersal AZ 16 safety gate switches or Pilz PSEN 1.1p position switches connect directly to the A1/A2 and S11/S12/S21/S22 terminals without modification. If the existing installation uses a Phoenix Contact PSR-MC-24DC/21-21/4X1/2X2 multi-channel safety relay as the master relay in a zone controller architecture, the PSR-SCP-24DC/ESP4/2X1/1X2 integrates as a subordinate relay in the same cabinet row, sharing the same DIN rail section and terminal block wiring convention.

For installations where the safety relay output drives a Siemens 3RT2 contactor or a Schneider Electric LC1D series contactor, the N/O output contacts of the PSR-SCP module are rated for the inductive load switching required by these devices, eliminating the need for interposing relays or surge suppressors in most standard machine safety applications. Where the control cabinet also houses a Phoenix Contact IB IL 24 DI 16-PAC inline digital input module or similar I/O slice for status feedback to the main PLC, the auxiliary N/C contact (41-42) of the PSR-SCP relay can be wired directly to a digital input channel to provide real-time safety relay status monitoring without additional signal conditioning.

In modernization projects where the host controller is a Siemens S7-1200 or S7-300 series PLC, no program changes are required — the PSR-SCP relay operates as a hardwired safety device upstream of the PLC I/O, and the PLC logic reads only the auxiliary contact feedback signal. Similarly, for systems using a Rockwell Automation Allen-Bradley GuardLogix or CompactLogix safety controller, the PSR-SCP module integrates into the hardwired safety circuit layer without requiring any EDS file configuration or safety network node assignment.

If the retrofit scope includes replacing aging Phoenix Contact PSR-SPP-24DC/URM/4X1/2X2 universal safety relays or PSR-SCP-24DC/ESD/4X1/1X2 emergency stop variants, the PSR-SCP-24DC/ESP4/2X1/1X2 serves as the recommended current-generation replacement, offering an upgraded safety integrity level (SIL 3 / PLe) while maintaining backward-compatible terminal assignments in most wiring configurations.

Retrofit Guidance FAQ

Q: Can I replace my existing PSR-SCP-24DC/ESD/4X1/1X2 with this module without rewiring?
A: In most cases, yes. Both modules share the same 22.5 mm DIN rail housing and screw terminal layout. Verify that your field wiring uses the same input channel configuration (single or dual NC contact) before swapping. No PLC program changes are required.

Q: Is the PSR-SCP-24DC/ESP4/2X1/1X2 compatible with my existing 24 VDC control cabinet power supply?
A: Yes. The module accepts 24 VDC ±20%, which is within the output tolerance of all standard Phoenix Contact, Siemens SITOP, and Schneider Electric Phaseo power supply modules used in industrial control cabinets.

Q: Do I need to modify my PLC program after replacing the safety relay?
A: No. The PSR-SCP relay operates as a hardwired safety device. The PLC reads only the auxiliary contact feedback signal (if wired). No logic changes, function block updates, or safety program re-validation are required on the PLC side.

Q: What communication protocol does this relay use?
A: The PSR-SCP-24DC/ESP4/2X1/1X2 uses a hardwired safety circuit — it does not require PROFINET, EtherNet/IP, PROFIBUS, or any other fieldbus protocol. It is fully compatible with any PLC platform.

Q: Will this module fit in the same panel space as my old safety relay?
A: Yes. The 22.5 mm DIN rail width is identical to the majority of PSR-SCP and PSR-PC predecessors. No panel cutout modification or DIN rail repositioning is required.

Q: How do I verify the replacement is functioning correctly after installation?
A: Perform a functional test by actuating the monitored E-stop or safety gate device and verifying that the output contacts open and the LED status indicator changes state. Then reset the relay using the monitored reset input and confirm the output contacts close. This test should be documented as part of your machine safety validation record.

Warranty Assurance

Every Phoenix Contact PSR-SCP-24DC/ESP4/2X1/1X2 (2981020) shipped by TOPNLMS is covered by a 12-month warranty from the date of delivery. Prior to shipment, each unit undergoes functional verification including input circuit continuity, output contact switching, and LED status indication checks. Units that fail pre-shipment testing are quarantined and not dispatched.

In the event of a warranty claim, TOPNLMS provides replacement dispatch within 3 business days of claim confirmation. Our after-sales team responds to technical inquiries within 24 hours on business days. All warranty replacements are shipped with the same pre-shipment test documentation as the original unit.

For procurement teams requiring traceability documentation, TOPNLMS can provide shipment records, test reports, and country-of-origin certificates upon request. Bulk orders for MRO stock replenishment or planned maintenance shutdowns are supported with lead-time confirmation and reserved inventory allocation.

Contact our technical sales team to confirm availability, request a quotation, or discuss compatibility with your specific installation before ordering.