Campbell Scientific LR4 Four Channel Latching Relay Module - Manual (Page 7)

LR4 Four Channel Latching Relay
Module
1. General Description
The LR4 module uses latching relays that provide the following benefits:
• Low power consumption
Once the control module changes the state of the relay by applying power
to a coil, power can then be removed as the relay mechanically latches its
state. Conventional relays require the power to be continuously present to
hold a relay in one of its states.
• Relay state is non-volatile
Once a relay is set to a desired state, the relay will remain in that state even
if power is lost to the control module. The only way to change the state of
a relay is to send a valid command that instructs the relay state to be
changed or by using the manual toggle button.
2. Specifications
Supply Voltage: 9 to 30 Vdc
Power Consumption
Quiescent:
< 2.0 mA
Peak: < 250 mA
Operating Temperature: -40º to +60ºC
Relay Type: Latching
Communications Hardware: SDI-12, RS-232, RS-485
Protocol: SDI-12 Version 1.3 or ModBus
via RS-232/RS-485 at 19,200 bps
Digital I/O Input Voltage
Maximum: +20
Vdc
Minimum: -12 Vdc
Dimensions: 17.0 x 6.1 x 3.7 cm
(6.7 x 2.4 x 1.5 in)
Weight: 0.48 kg (1.05 lb)
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