Water Level Sensor
This water level sensor is conducive for liquids that have a conductivity of equal to or more than 25m Siemens. The system is economical to install as no special cable is required for signal transmission. The level probe and the evaluation unit can be connected using a long cable. The AC is provided on the probe for preventing electrode deterioration.
You can choose from among a variety of level control and installation systems such as
- Two point sensors for independent switching and automatic control of pump.
- Four point switching with two pump control logic.
- Three point switching: two for pump control logic and one independent point with or without a settable delay (for probe covered or uncovered).
- A variety of probes is available for your specific process.
Applications of SLW Water Level Sensor
The SLW... series water level switches work to maintain a constant water level avoiding material wastage in your process plant. Common applications include switching pumps on and off to avoid overflow, dry running and indicating water level in an empty tank to avoid wear and tear and production stoppage. Many of our customers in the Food, Power, Chemicals, Sugar, Detergent, Steel, Minerals and Textile industry have used the SLW... series water level indicator.
Principle of Operation - SLW - Water Level Indicator
A low AC voltage is applied between the probe electrode and the tank wall (or reference electrode in case of insulated tank). When the water/liquid comes in contact with the electrode tip, a conductive path is established between the sense electrode and the tank wall/reference electrode. This current is sensed, amplified and made to operate a relay whose contacts in turn can be used for annunciation/control.
SLW Water Level Sensor Evaluation Unit
|Housing||Cast aluminium, Weather-proof Stoving enamel painted suitable for back panel/wall mounting.|
|Cable Entries||3 Nos. of 1/2 “ BSP|
|Mains||110 or 230 V AC (-15 to + 10%) 50 Hz (as specified in order).|
|Relay Output||One set of potential free change over contacts rated at 6A 230 V AC, 50Hz for non-inductive load.|
|Power Consumption||5 VA approx.|
|Fail-Safe Mode||High or Low field selectable.|
|Response Time||0.5 second|
|Switching Delay||0.5 to 20 seconds for probe covered and uncovered condition|
|Maximum Sensitivity||25 Micro Siemens|
|Operating mode||(A) Single point switching.|
(B) Two-point switching with pump control logic.
|Indication||Red LED for Alarm, Green LED for Normal.|
|Mounting||1½” BSP Screwed or Flanged mounting.|
|Operating Temp.||-20º C to + 60º C.|
Water Level Sensor - Level Probe
|Voltage||12 V AC (across probe & tank wall/ grounding electrode)|
|Current||<4 mA (between probe & tank wall/grounding electrode through liquid)|
|Operating Temp.||Up to 80º C (Standard model) |
Up to 200º C (Optional)