UDZ Electrical Contact Measuring Cylinder

Deskripsi

Electrical Contact Measuring Cylinder

I. Uses and Features

The UDZ series electric contact water level gauges are mainly used for monitoring the water level of boiler drums, high-pressure heaters, low-pressure heaters, deaerators, evaporators, condensers, once-through boiler start-up separators, and water tanks of dual water-cooled generators, as well as for measuring the water level of other conductive liquids. However, they are not suitable for flammable or explosive media.

II. Working Principle

Because water and steam have vastly different electrical conductivity, the measuring cylinder’s function is to transmit water level changes as signals through changes in the resistance of the electrical contacts. The insulators at the electrical contacts insulate the contacts from the outer shell of the measuring cylinder. In the liquid state, due to the low resistance of water, the contacts are connected to the outer shell. When an AC voltage is applied between the contacts, the current flowing through is large, causing the integrated operational amplifier in the secondary instrument to flip, and the color-changing LED on the panel displays “green.” Conversely, when the contacts are not submerged in liquid, they are in a vapor state. Because steam has a high resistance, it can be considered a relatively open circuit, resulting in a smaller current flowing through it. The integrated operational amplifier in the secondary instrument does not flip, and the color-changing LED on the panel displays “red.” Therefore, the water level depends on the number of contacts submerged, i.e., the number of “green” LEDs.

III. Main Features

The UDZ series water level gauge mainly consists of a measuring cylinder, electrical contacts, and a secondary instrument. It utilizes the significant difference in conductivity between water and steam within the boiler drum to convert changes in water level into changes in resistance via electrical contacts, which are then transmitted to the secondary instrument for measurement, display, and control. The design employs a multiple-contact detection method; the number of electrical contacts on the measuring cylinder corresponds to the number of display points on the secondary instrument, with a maximum of 19 points and up to 21 points in special models (using a 160*80*200mm housing).

The electrical contacts of the UDZ series water level gauges are made of ultra-high purity ceramic electrodes, which have excellent pressure resistance, temperature resistance, and insulation performance. They are powered by AC, which effectively extends the life of the electrical contacts and avoids the hassle of frequent contact replacements for users.

IV. Main Technical Parameters

Instrument naming method: Product type—Measuring cylinder—Pressure—Number of points—Application—Installation method—Secondary instrument—Water resistance

Measuring cylinder: 01S—Working pressure ≤4.41Mpa; Working temperature: ≤250℃

02S—Working pressure: ≤15.68 MPa; Working temperature: ≤350℃

03S—Working pressure: ≤20.6 MPa; Working temperature: ≤400℃

Connecting pipe specifications: DN15 flange or welded, DN20 flange or welded, DN25 flange or welded, and other sizes can be customized. Electrical contact bolt holes are M16X1.5. For special orders, the distance between two contacts on the same side must be ≥60mm.