Model ARP120A6R

  • $53.75
Shipping calculated at checkout.

Description Of Function

In the off state, the Control Switch is open, the Alternating Relay is in the LOAD 1 position, and both LOAD 1 & LOAD 2 are off. The red LED marked "LOAD 1" is ON. When the Control Switch closes, it energizes LOAD 1. As long as the Control Switch remains closed, LOAD 1 remains energized. When the Control Switch opens, LOAD 1 is turned off and the Alternating Relay toggles to the LOAD 2 position. The red LED marked "LOAD 2" is ON. When the Control Switch closes again, it energizes LOAD 2. When the Control Switch opens, LOAD 2 is turned off, the Alternating Relay toggles back to the LOAD 1 position, the red LED marked "LOAD 1" is ON, and the process can be repeated.

Product Overview

  • For Duplex Control of two loads
  • Optional low profile selector switch to lock in one sequence
  • 2 LEDs indicate relay status
Enclosure Style

Plug-in case utilizing industry-standard octal sockets

Configuration / Contact Rating
  • 10A @ 240V AC/24V DC, 1/2HP @ 120/240V AC (N.O.), 1/3HP @ 120/240V AC (N.C.)
Application Information
  • Voltage Tolerance: AC Operation: +10/-15% of nominal at 50/60 Hz.; DC Operation (12 & 24V only): +10/-15% of nominal.
  • Load (Burden): Less than 3 VA
  • Indicator LEDs: Two LEDs marked LOAD 1 and LOAD 2
  • Life: Mechanical: 10,000,000 operations; Full Load: 100,000 operations
  • Temperature: -28° to 65° C (-18° to 149° F)
UL #: E109466
URCSACEUL Listed with Socket

ARP Series:

  • Plug-in enclosure uses standard 8- or 11-pin octal socket
  • Duplex control of two loads
  • SPDT, DPDT and DPDT Cross-Wired output

Equalizing run times increases equipment life and provides additional capacity.


Alternating Relays are used in applications where the optimization of load usage is required by equalizing the run time of multiple loads. When identical loads are used for the same jobs, a standby unit is typically available in case the first load fails. However, an idle standby unit might deteriorate due to lack of use and is not a reliable backup. Alternating relays prevent this by assuring that multiple loads get equal run time.


Alternating Relays can also be used where multiple loads are on at the same time for additional capacity, if one load cannot keep up with demand. This alternating action is normally initiated by a control switch such as a float switch or pressure switch. Each time the initiating switch is opened, turning off a load, the alternating relay will change state, thus alternating between multiple loads. Typical applications include pump/motor units with float switches as the initiating contact, or compressors with pressure switches, or thermostats as the initiating contact.


Macromatic offers two types of Alternating Relays: Duplexor: For controlling two loads with both plug-in (ARP Series) and Flange enclosure (ARF Series) for inner-door mounting, in SPDT, DPDT and DPDT Cross- Wired output configurations. ARP Series Duplex Controllers provides Sequence On - Simultaneous OFF (S.O.S.O.) operation with three switch inputs. Triplexor: For controlling up to three loads with plug-in enclosures (ATP Series). An optional top-mounted switch allows it to be used as a Duplexor until system expansion requires an added third load.