Relay Drivers / A21REL-12

Overview

The A21REL-12 contains four internal relays that allow a Campbell Scientific datalogger to control up to four external ac or dc devices.


Detailed Description

The A21REL-12's internal relays are single-pole double-throw. This relay driver may be powered by the datalogger power supply or a separate 12 Vdc battery.

Specifications

  • Contact Ratings: 1 A at 20 Vdc;
    0.3 A at 120 Vac
  • Coil Current: 13 mA/relay
  • Relays: dual single-pole, double-throw relays
  • Operating Temperature: -25° to +50°C
  • Dimensions with connectors:
    14.0 x 6.9 x 3.0 cm
    (5.5" x 2.7" x 1.2")
  • Weight: 227 g (8 oz)

Compatibility

Datalogger Considerations

Each of the four relays is controlled by a datalogger control port.

Compatible Contemporary Dataloggers

CR200(X) Series CR800/CR850 CR1000 CR3000 CR9000X

Compatible Retired Dataloggers

CR500 CR510 CR10 CR10X 21X CR23X CR5000 CR7X CR9000
* *

Notes:
*The CR500 and CR510 only have one control port capable of providing a control signal.


Cables

Cable(s) Used Number of Relays Controlled
One CABLE3CBL-L 1
One CABLE4CBL-L 2
One CABLE5CBL-L 3
Two CABLE3CBL-L 4


Power Considerations

The A21REL-12 may be powered by the datalogger power supply or a separate 12 Vdc battery.


Enclosure Considerations

The A21REL-12 requires a non-condensing environment. No mounting bracket is available. The peripheral is typically mounted in the datalogger enclosure with double-sided tape or Velcro.

Compatible Enclosures

ENC10/12 ENC10/12R ENC12/14 ENC14/16 ENC16/18 ENC24/30 ENC24/30S

Documents


Frequently Asked Questions

Number of FAQs related to A21REL-12: 1

  1. The following relay devices can be used with the CR800 and the CR850:

    • 7321
    • A6REL-12*
    • A21REL-12
    • LR4
    • SDM-CD8S
    • SDM-CD16AC
    • SDM-CD16S

    The CR800 and the CR850 can also be used with a wide variety of third-party relay devices.

    *Because the CR800 and the CR850 only have four control ports, they do not have the ability to switch all six of the relays on the A6REL-12.

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