1SNA645036R2500 ABB RB121PG-5VDC R600 5 V DC Interface Relay 1 c/o 3 mA-6 A
ABB RB121PG-5VDC R600 interface relay, order code 1SNA645036R2500, featuring a 5 V DC polarised control input, 1 c/o gold-plated contact and 3 mA-6 A switching range for industrial automation and control applications.
The ABB RB121PG-5VDC, order code 1SNA645036R2500, is a compact R600 series interface relay designed for reliable electrical isolation, signal matching and switching in industrial control and automation systems. Featuring a 5 V DC control supply and a single changeover contact, it provides an effective interface between low-voltage control equipment and switched loads.
As part of the ABB R600 boxed interface relay range, the RB121PG-5VDC combines a slim 6 mm width with screw-terminal connections for space-efficient installation in control cabinets. Its gold-plated silver-tin-oxide contacts support reliable switching of low-current signals, while the built-in LED provides clear visual indication of relay operation.
The RB121PG-5VDC provides 1 c/o (SPDT) contact with a switching range of 3 mA–6 A and a maximum switching voltage of 250 V AC. Its 5 V DC polarised A1-A2 control input and compact DIN-rail format make it particularly suitable for PLC interfaces, machinery, process control and general industrial automation applications.
Key Advantages
Compact ABB R600 interface relay for industrial control and automation applications.
5 V DC rated control supply voltage suitable for low-voltage control circuits.
Compact 6 mm-wide housing for high-density control-panel installations.
Reliable Signal Switching for Industrial Automation
Interface relays provide an electrical link between control electronics and field loads, enabling low-voltage signals from PLCs, controllers and other automation equipment to operate separate circuits. The ABB RB121PG-5VDC combines this interfacing function with electrical isolation and a compact form factor suitable for densely populated industrial control panels.
The R600 series is designed to provide space-efficient relay interfacing with straightforward installation and wiring. With its 5 V DC polarised input, gold-plated changeover contact, screw terminals and integrated LED, the RB121PG-5VDC is well suited to applications requiring reliable low-current signal switching and clear operating-state indication.
Typical Applications
PLC input and output interfacing.
Industrial control and automation panels.
Low-current signal switching.
Electrical isolation and signal matching.
Machine control circuits.
Process-control equipment.
Building automation and control systems.
OEM machinery and production equipment.
Technical Specifications
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Terminal Type
Screw
Mounting Type
DIN rail
Load Voltage
250 V AC
Series
R600
ABB order code
1SNA645036R2500
Product group
310923 - Interface Relays & Opt. Couplers
Product type
Boxed interface relay
Rated control supply voltage
5 V DC
Output contacts
1 c/o (SPDT)
Switching range
3 mA–6 A
Maximum switching voltage
250 V AC
Control input
A1-A2 polarised
Terminal type
Screw terminals
Contact material
Gold-plated silver-tin-oxide (AgSnO2/Au)
Indication
Built-in LED
Protection rating
IP20
Mounting type
DIN rail
Width
6 mm
Height
67.5 mm
Depth
70 mm
Dimensions (H × W × D)
67.5 × 6 × 70 mm
Net weight
0.02 kg
Frequently Asked Questions
What is the ABB RB121PG-5VDC used for?
The ABB RB121PG-5VDC is an R600 interface relay used for electrical isolation, signal matching and switching between control equipment such as PLCs and loads in industrial automation systems.
What control voltage does the RB121PG-5VDC require?
The relay has a rated control supply voltage of 5 V DC and uses a polarised A1-A2 control input.
What contact configuration does the RB121PG-5VDC have?
The RB121PG-5VDC provides one changeover contact (1 c/o or SPDT) with gold-plated silver-tin-oxide contacts.
What is the switching range of the ABB RB121PG-5VDC?
The relay has a switching range of 3 mA–6 A, making its gold-plated contact particularly useful for applications involving low-current control signals.
How wide is the ABB RB121PG-5VDC?
The RB121PG-5VDC is only 6 mm wide, enabling high-density DIN-rail installation in industrial control cabinets where panel space is limited.
Trusted Industrial Control from ABB
ABB R600 interface relays provide compact and dependable signal switching for industrial automation, machinery and control-panel applications, combining space-efficient installation with practical connection, indication and electrical interfacing features.
Terminal Type
Screw
Mounting Type
DIN rail
Load Voltage
250 V AC
Series
R600
ABB order code
1SNA645036R2500
Product group
310923 - Interface Relays & Opt. Couplers
Product type
Boxed interface relay
Rated control supply voltage
5 V DC
Output contacts
1 c/o (SPDT)
Switching range
3 mA–6 A
Maximum switching voltage
250 V AC
Control input
A1-A2 polarised
Terminal type
Screw terminals
Contact material
Gold-plated silver-tin-oxide (AgSnO2/Au)
Indication
Built-in LED
Protection rating
IP20
Mounting type
DIN rail
Width
6 mm
Height
67.5 mm
Depth
70 mm
Dimensions (H × W × D)
67.5 × 6 × 70 mm
Net weight
0.02 kg
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UK delivery
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This productManufacturer Lead Time
Estimated Delivery 4 - 5 Days
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LED Controls is a specialist distributor of factory automation and industrial controls, supplying OEMs, machine builders, panel builders and end users throughout the UK and worldwide. As a trusted UK distributor for many of the world’s leading automation manufacturers, we provide industrial control products, technical expertise and bespoke automation solutions backed by outstanding customer service.
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