Campbell Scientific Ltd., Campbell Park, 80 Hathern Road, Shepshed, Loughborough, LE129GX,UK

Tel: +44 (0) 1509 601141 Fax: +44 (0) 1509 601091 Email: sales@campbellsci.co.uk

www.campbellsci.co.uk

LR4 4-Channel Latching

Relay Module

Features

February 2011

CSL 809

The LR4 Four-Channel Latching

Relay Module is ideal for

locations where power is

unreliable or needs to be

conserved. Unlike traditional

relays that must be continuously

powered to keep their state, the

LR4 mechanically latches the

relay’s state allowing power to

be removed. The only way to

• Low power

consumption

• Relay state is non-

volatile

• 4 channels

• LED indicators

• Manual toggle

override for each

relay

• Compatible with all

SDI-12 capable

dataloggers

LR4 Four-Channel Latching Relay Module

Relay Details

Contacts

Relay #1 and Relay #2

2 independent; single pole single throw (SPST)

Relay #3 and Relay #4

2 independent; single pole double throw (SPDT)

Maximum Voltage Ratings: 30V DC/30V AC

Maximum Current:

Relay #1 and Relay #2

Not to exceed 100V A or 5 A

Relay #3 and Relay #4

Not to exceed 60V A or 2 A

change the state of a relay is to

send a command to the LR4 or to

press the manual toggle button.

The datalogger sends commands

to the LR4 via the SDI-12 protocol

or ModBus protocol.