Flow Switch Alarms

Float switches are a very simple and reliable way of monitoring fluid levels in tanks and pump stations, they are set at fixed levels at the time of commissioning and signal for high/low levels and are used to turn pumps on and off. In the most simple type of application, a float switch can give early warning of a tank reaching capacity, this is used in fluid storage tanks such as cesspools and holding tanks. It can also be used in process tanks and pump stations to give warning of any backup in the system. Multiple float switches can be fitted to tanks to give a degree of level monitoring. SPEL pump stations use float switches for ‘pump on’, ‘pump off’, and ‘high level’. This can be further added to with both ‘high-high level’ and for activating a second pump, in duty assist configuration.

SPEL LR30 Control Panel

The SPEL LR30 alarm operates from a switched input, such as a float switch or pressure switch. The alarm can be activated either by a closed circuit switched input or an open circuit switched input.

Once activated, the alarm provides a visual and audio indicator. There is an option to connect an external beacon or other circuitry via the auxiliary output and/or the volt free relay output.

A mute button allows the operator silence the audio alarm of the unit without affecting the visual, auxiliary output or volt free relay output of the alarm.

A test button conveniently allows the operator to check the alarm functions without the need of triggering the input to the alarm.

Power to the alarm is indicated via a blue constant light, allowing easy operational inspection of the unit.

Typical uses for this alarm are high or low-level warnings in water treatment tanks.

Control unit	Rating
Enclosure:
IP Rating	IP65 rated
Dimensions	230 x 120 x 100mm
Weight	0.7kg
Supply Voltage
Minimum	110Vac [50/60Hz]
Maximum	240Vac [50/60Hz]
Fusing	250mA [Internal]
Switched Input
Max cable length	200m
Switched voltage	5Vdc
Max switched current	10mA
Audio Output
Max sound level	105dB
Visual Alarm Output	Red flashing LED
Output Relay
Relay topology	SPDT [COM/NO/NC]
Max current	10A @250Vac
Max voltage	250Vac
Auxiliary Output
Voltage	12Vdc
Max current	250mA [3W]
Terminal Capacity	0.2-4mm² [tool free wire fitting]
Ambient Temperature	-10°C to +55°C