电接点水位计英文说明书.

China Jiangsu

Taicang Instrument Factory

Taicang Computer Application Instrument Factory

Product Specimen

Product Manual

SXY2 series liquid level monitor SWJ series electrode water level meter

Brief Introduction

Taicang Instrument Factory and Taicang Computer Application Instrument Factory covers an area of 5640 sqm and their floor area is 3000 sqm. There are 144 staff and workers among which 8 professional inspectors and 15 engineers, assistant engineers and economists. The factories are capable of producing in batches the complete set of electric contact water level meters which obtain the title of famous brand product of Suzhou City. The factories have been praised as the “bona fide”unit successively for ten years.

Established in 1977, Taicang Instrument Factory mianly produces instruments, valves, electrodes and high pressure vessels etc. All these products sell well to about 800 users in 28 provinces, cities and autonomous regions and the products are also supplied to a considerable number of boiler manufacturers. The products also enjoy exportation to southeast Asian regions. Now they have developed J641Y-64 pneumatic fast shutoff valve, J61Y-P55 170V high pressure cutoff valve, pressure vessel, B43H pipe level meter and DK,-3 single and double polarity switch etc.

Taicang Factory is equipped with processing machines as lathes, grinders, millers, drillers, cold processing and welding equipment. It also has electronic measuring instruments, transistor characteristice display instruments, BT-3 frequency characteristics display instrument, UJ-37 electronic display instruments, BT-3 frequency characteristics display instruments, UJ-37 electronic potential difference gauges and standard resistor box etc.

Taicang Instrument Factory and Taicang Computer Application Instrument Factory is designated as the SWJ series and SXY2S series electrode two-colour water level meters producer by The Ministry Of Machinery And Electronics Industry.

1.Application

SXY2S series liguid level monitor is a new kind of electrode liquidometer, which is suitable for measuring and controlling the liquid level in boiler drum, high and low pressure heater, degasifier, evaporator, start-up separator of once-through boiler, water tank etc. It is also used for measuring and controlling the level of other electric conductive liquid, but not for the combustibe, burstable or corrosive liquid.

For meeting the demand of increased water treatment technology, the instrument could be used in the situation of water resistance 0~500KΩ, the function of adjusting water resistance arbitrarily is designed in the instrument for consumer’s using in situ.

2.Technical parameters

1.V oltage requirement: 220V(-15% ~ +10%)

2.Supply time of direct current(D.C)by storage battery in the instrument:≤4hours

3.Operating temperature: -10℃~ +45℃

4.Operating humidity：≤85%

5.Suitable water resistance：0-500KΩ

6.Down lead length from contact to indicator instrument：≤200m

7.Capacity of output contact of relay：maximum limited two sets in normally open and normally

shut 220V 3A, minimum limited two sets in normally open and normally shut 220V 3A(the instrument with the relay of maximum limited three sets and minimum limited two sets could be provided according the special requiment of user).

8.Hole in a instrument panel for mounting:152+1mm×76+1mm

9.Dimensions:80mm×160mm×300mm(W×H×L),special type:160mm×160mm×300mm

10.Power consumption:≤5W

11.Weight: about 2.8Kg

3.Nomenclature

SWY2S-XXX-XXX-X

Product type-scale type-measure cylinder-erect mode (function)

The scale type look up table 6, The measure cylinder look up table 2, erect mode: Z-vertical, H-horizontal ,C-self-provided power source

4.Characteristics

1.SXY2S series liquid level monitor consists of measure cylinder, electrode contacts and secondary meter. On the priciple of different conductivity between water and steam in the boiler drum, the change of water level could be transformed into the cgange of resistance, which then be delived to secondary instrument to measure, indicate and control. The multi-polar detection is adopted, i.e, the numbers of electrode contact in measure cylinder is same as the number of indicated point on secondary meter. The most number of electrode contact is 38 (for special type 160mm×160mm×300mm).

This electrode contact liquidometer could be suited to the boiler operation conditions with changed paraments, such as start-up or shut down In such operation conditions, the drum level could be indicated exactly also. Because of the larger sectional area of the measure cylinder, the shrinkage

error caused by decrease of water temperature is very little. And the measure cylinder is near to the drum with electric signal transfer from electrode contact to secondary meter , so that the time delay is very short.

2.The ultra-pure ceramics electropolars are used as electrode contacts fitted in SXY2S series liquid level monitor, which have excellent characteristic of pressurization, thermostability, insulation and use alternating current as power supply, so that the life of electrode contact could be prolonged effectively, the troble of changing electrode contact frequently could be avoided.

3.The integrated circuit with high input resistence and CMOS digital circuit with socket are used in secondary meter,it is very convenient for production and maintenance. The analog display and digital display are used simultaneously as indicator of the instrument,so the up-down situation of the water level could be indicated very sensitively. A set of colour changeable luminant diodes matched with a standard scale-meter are used as analogy display, red as steam while green as water. While a three digits LED charactron matched with a sign indicator is used as digit display (four digits charactron is used in some instruments).

4.The SXY2S series liquid level monitor is provided with the function of acousto-optic alarm when the water level is beyond the limit. The alarm point could be setted arbitrarily according the user’s demand (jumper wire connection is adopted), and each two sets of relay’s output control contacts as higher limit and lower limit respectively are provided for extemal connection. To the special demand, the output control contacts of three sets as higher limit and two sets as lower limit (or two sets as higher limit and three sets as lower limit) could be provided also. For eliminating the effect of false level on the alarm interlock action caused by getting water drop on the electrode, the judge fuction of alarm logical control is designed specially to avoid alarm of false level effectively. Besides, for avoiding the different kinds of interference caused by all sorts of thermal instrument and equipmetn in control room.as well as long distance transfer of signals, the higher interference protection measure is adapted in design of the present series instrument.

5.In order to ensure boiler operation normally, when power supply suddenly stop the water level could be detected and alarmed still, the power self-supplying fuction is set up to supply power more than 4 hours after power accident by butteries in the instrument.

6.The quick detecting button is fitted on the panel of instrument for checking the troble place of secondary meter conveniently.

7.The blowdown button is also fitted on the instrument panel for avoiding malfunction and misalarm caused by attracting the control contacts of two sets of lower limit relay when measure cylinder doing blow-down.

5.Structure and Function

1.Measure cylinder

Its structure is shown in Fig.1.

Centerline spacing of vapour-liquid commumicating tube

Fig1Structure of measure cylinder

The functions of every parts are shown in table 1.

demand of user.

The specifications of measure cylinder are shown in table 2.

According to the National Machinery Trode Standard

2.Electrode using ultra-pure ceramics electropolars

working temperature≤37.2

pressurization≤21.56Mpa

insulating property＞500MΩ

The specifications of electrode are shown in table 3.

3.Secondary meter

1)front panel

It is shown in Fig.2.

muffle

Blow down

Fig 2Front panel

The functions of every part of front panel are shown in table 4.

Table 4 Functions of every part of front panel

2) rear panel

It is shown in Fig.3.

The functions of every part of rear panel are shown in table 5.

Fig.3 Rear panel

RS232-15 pins

fuse socket

toggl switch

RS232-25 pins socket

two fastening screws

6 Operating principle

1.Operating principle of system

SXY2S sieres liquid level monitor system consists of measure cylinder electrods and secondary meter. Its functional schematic diagram is shown in Fig4.

Fig 4. Functional schematic diagram of system

Because the conductivity of water is very different from that of steam the function of measure cylinder is to get the signal of resistance ’s changing of electrode as water level changes. Owing to the smaller resistivity of liquid medium, the current passed through electrodes is large when a electric voltage put on between electrodes. On the contrary, the current passed through electrldes is small as the electrodes are above the liquid level. The current difference of such two conditions is very large. It could be as a signal sending to secondary meter. After amplifying, it could be displaied and could control output. So the long-distance supervisory control is realized. 2.Operating principle of secondary meter

Its functional schematic diagram is shown in Fig.5. The electricity schematic diagram is shown in attached figure(SXY2S-19c as example)

(1)detect and simulate display unit

Since every electrode contact is corresponding to a route of detect and simulate display unit, so there are 19 electrode contacts corresponding to 19 routes of detect and simulate display unit. Every route of detect and simulate display unit consists of same detecting element, display drivecircuit and colour-changeable luminant diode, shown in Fig.6.

steam-water commuicating valve

measured vessel

m e a s u r e d c y l i n d e r

wire

blow down valve

level display

r e l a y o u t p u t

Secondary meter electrod

d i g i t d i s p l a y u m i t

diode encoder

Fig5 Functional schematic diogram of secondary meter

Fig.6 Detect and simulate display circuit

圖6 檢測和模擬顯示電路圖

When the electrode contact is not under liquid, owing to large resistivity of steam, the current passed through the electrode contact put from alternating signal power source is small which cuts the detecting biode D1 off. The integrated circuit puts out negative voltage(about –2V). So colour-changeable luminant biode back conducts and displays red.

When the electrode contact is under liquid, owing to small resistivity of liquid, the current passed through the electrode contact put from alternating signal power source is large, which connects the detecting biode D1 on. The integrated circuit puts out positive voltage(about +3V). So colour-changeable luminant biode forward conducts and displays green.

The output voltage signal of integrated circuit is sent to digital display circuit and logical control alarm circuit simultaneously, which numbers are B1-B19 respectively from low to high.

(2) digital display circuit

Its functional schematic diagram is shown in Fig.5. B1-B19 are the input signals of digital display circuit, the higher electrical level is +3V, the lower one is –2V: Whe the hight of liquid level changes, the electrical level of B1-B19 signal changes responsively. First the B1-B19 signalprior encode through three 4532 circuits, then address latch by three 4099 circuits, decoding by biode matrix, last the figure of the liquid level is displaied through four 45H circuits, which drives one digit symbolic identifier and three digits caractron, This figure shoule be consisitent with the value indicated on the scale of liquid level.

(3) logical control alarm circuit

Its functional schematic diagram is shown in Fig.5. B1-B19 are the input signals of logical control circuit, which could be connected with jumper wire according to the different demand of user’s conditions.

The higher limit logical control circuit consists of AND gate 1,2,3, which four input terminals are H1,H2,H3,H4 in order. When the input signals of logical control circuit connected from H1,H2 are high electrical level, i.e. corresponding electrode contacts are under liquid, the output s1 becomeshigh electrical level. So the alarm lamp(yellow) of higher limit is lighted, the buzzer issues alarming sound. Meanwhile the relay J3 of higher limit is acted by the control of integrated circuit. If one signal of H1 and H2 is low electrical level. The SI is low electrical level still, the alarm of light and sound, as well as relay are not acted. So it is effective to prevent wrong alarm of false water level.

When the signals of H1,H2,H3 are all high elevtrical level, the output S2 becomes high electrical level. So the alarm lamp (red) of maximum limit 1 is lighted, the buzzer issues alarming sound. Meanwhile the relay J4 of maximum limit 1 is acted by the control of integrated circuit.

Similarly, when the signals of H1,H2,H3,H4 are all high electrical level, the output S3 becomes high electrical level. So the alarm lamp (red) of maximum limit 2 is lighted, the buzzer issues alarming sound. Meanwhile the relay J5 of maximum limit 2 is acted by the control of integrated circuit.

The lower limit logical control circuit consists of AND gate 4.5, which four input terminals are L1,L2,L3,L4 in order. When one signal of L4,L3 is low electrical level, I,e. one of the two corresponding electrode contacts is above liquid level, the output X2 becomes low electrical level. This means that the liquid level decreases below the alarm point of lower limit. So the alarm lamp (yellow) of lower limit is lighted, the buzzer issues alarming sound. Meanwhile the relay J2 of lower limit is acted by the control of integrated cireuit.

Similarly, when one signal of L2,L1 is low electrical level, the output X1 becomes low electrical level. This means that the liquid level decreases below the alarm point of minimum limit. So the alarm lamp(red) of minimum limit is lighted, the buzzer issues alarming sound. Meanwhile the relay J1 of minimum limit is acted by the control of integrated circuit.

(4) optional function of alarm point

Considering the generality of SXY2S series liquid level monitor and the demand of user’s changing alarm point, the jumper wire connection mode is adopted to achieve the goal of changing alarm point.

For example:there is a miter of SXY2S-19C, which has a scale of 0,±15,±30,±50,±75,±100,±150,±200,±250,±300. The alarm points are set as +50,+200 in manufacture. If the alarm points should be changed as ±75,±250 according the demand of user, the connect wire of alarm points could be changed as:

higher limit and maximum limit: B13 connects to H1,B14 connects to H2,B18 connects to H3(B13 corresponds to +50,B14 to +75, B18 to +250).

lower limit and minimum limit: B6 connects to L4, B5 connects to L3, B2 connects to L2, B1 connects to L1 (B6 corresponds to –75,B5 to –100,B2 –250,B1 to –300).

(5) Power source

AC 220v is as power source as SXY2S series liquid level monitor. After voltage transform, rectification, filtration, voltage stabilization, +6v working voltage could be got to supply every circuit.

Becides, 15V alternating modulating current got through a oscillation which consists of NE 555circuit, is connected to circuit of electrode contact. So the alterneting current supply mode is adopted for electrode contact’s working,

There are batteries in the instrument, When AC200V power supplies normally, after voltage stabilization, +6V working voltage is got to charge two sets of battery floatingly. If AC200V power was interupted, two sets of battery could be connected to instrument’s circuit automatically by two electronic switches, which consist of transisitor circuit, to guarantee instrument work normally. After AC power accident, the two sets of battery could supply power more than 4 hours in the condition of full charge.

(6) quick detecting function

Three is a quick detecting button on the panel of instrument for users quickly detecting the cause of troble. When the quick detecting button is pressed down, the all electrode contacts are simulated in the condition of under liquid, so the all colour changeable luminant diodes displaygreen. If anyone of the diodes is dark or red, that means this diode and its related circuit has troble. If one of the diodes does not display green in the condition of under liquid as normalwork, but it could display dgreen as detect, that means the electrode contact related to this diode or the connect wire between the electrode contact and secondary meter has troble.

When the quick detecting button is pressed down, the all alarm relay contacts of higher limit and maximum limit are cut off.

(7)function of blowdown button

When the blowdown button is pressed down, the all alarm relay contacts of lower limit and minmum limit are cut off, and the blowdown of measure cylinder could be carried on.

7.Install and Connection

1.Measure cylinder and electrode contacts

(1)Before installation, the body of measure cylinder should be washed by carbon tetrachloride or other detergent, cleaning greasy dirt and iron chips.

(2)The measure cylinder must be erected vertically.

(3) The measure cylinder and measured vessel are connected by two tubes, which link to steam space and liquid space of vessel respective. The certain valves are erected on the two tube lines in order to

replace eletrode contact in operation.

(4) Before the electrod contacts are erected on measure cylinder, a little gredag should be spreaded on the thread in order to maintain and replace them.

(5) The blowdown of measure cylinder should be carried out periodically in operation.

(6) The connecting wire should be installed according to the field wiring diagram, keeping from the places of high temperature and moisture a certain distance.

2.Secondary meter

Before installation, the secondary meter could be detected by SCF-type special detecting instrument with a 25-pin plug and a 15-pin plug. After supplying 220V alternating current, forrowing contents should be detected:

a.functional detection of display unit

When the signal switches of K1-K19 are put on the location of “off”, the colour-changeable luminant diodes on the front panel should be lighten red respondingly. When K1-K19 are put on the location of “on”one by one, the diodes should be lighten green respondingly. Besides, the digit display should be in accordance with the scale display.

b.functional detection of logical control and alarm circuit

When K1-K19 are put on the location of “on”or “off” one by one, the alarm sound and light should be occurred in the responsive alarm point, meanwhile responsive relay should be acted, the indicative lamps of relay contact in the detecting instrument should be acted as red lamp “on”, green lamp “off”.

c.functional detection of quick detecting

Pressing down the quick detecting button on the front panel, the colour-changeable luminant diodes on the front panel should be displayed green all, the alarm relay of higher limit is cut off. Loosing the pressed button, the meter returns to the normal condition.

d.functional detection of blowdown button

Cuting off all switches of K1-K19 and pressing down blowdown button, the indicative lamp of blowdown is lighten and the alarm relay of lower limit is cut off.

e.functional detection of muffle

In the alarm range between higher limit and lower imit pressing down muffle button, alarm sound should be stopped, alarm light should be keeped still, the position of alarm relay contact is not changed.

After detecting as above, if meter is normal, then it could be put into operation.

3.Connection mode

The field connection mode is shown in enclosure 1.

图8 SXY2液位监控仪外部接线图SXY back wiring diagram

RS232-25

measure cylinder

blowdown tube

Fig.7 Field connection mode

The socket connection of secondary meter is shown in Fig.8. notice: don’t misconnect! Besides, what showing in Fig.8 is only the output conection mode of two sets of higher limit and lower limit of relay respectively. As to the output connection mode of three sets of higher limit and two sets of

4.Water resistance regulation

The water resistance range suited for SXY2S series liquid level monitor is 0-500K. When user place an order for the monitor, the water resistance range in usage condition should be given clear indication, so that we will try our best to regulate water resistance at best condition as the monitor manufactured. Besides, if the water resistance range was not given as ordering, the water resistance could be regulated to be 120K as manufacture. If the water resisrance in usage condition is larger or little than 120K, causing its work unusual, the secondary meter could be opened, the trimmer potentiometer at the back of meter panel could be regulated slowly by a metal turnscrew untill to the condition that liquid level could be indicated normally.

8.Trouble’s overhaul

Here gives some quadratic instrument’s normal troubles and the methods of how to judge and overhaul them. It’s for freference only to the users.

The first trouble:All functions of the instrument are out of work. There is no display on the panel.

Analyse and overhaul: (1) If the fuse has melted, please examine if there is short circuit or overload, and then a new fuse should be replaced.

(2)The power switch no longer has any effect. After cut off the electricity supply, open theinstrument’s inner parts, measure each contact of the power switch by the multimeter’s ohm detector in order to know their on-off situation and check whether the wire is out. When the switch is confirmed to be damaged, it should be replaced by the same standard switch.

(3) AC 220V is broken off.(only to not have self-power supply)

After supplying electricity, switch on.

(4) The power transformer is no longer in force (only to not have self-power supply). Open the inner parts, measure the on-off situation of the primary coil and secondary coil of the power transformer and the situation of the wiring by the multimeter’s ohm detector. Wher the transformer is confirmed to be damaged, it should be replaced.

The second trouble:All the colour-changeable luminant diodes on the panel show red after the instrument supplying electricity, and can’t indicate the state of liquid level.

Analyse and overhaul: Press the fast measure push button, if the diode on the panel all show green, examine the following respects:

(1)The 25-pins plug isn’t inserted on the back panel well. It makes the electrode contact signal can’t enter instrument, and it should be inserted again.

(2) The AC 15V modulation power used in electrode contact operation isn’t added. Please examine the oscillator’s each element related to modulation power which produce the AC15V and wiring etc, in order to see if there is any abnormal phenomena.

Because the instrument’s water resistance is adjusted inappropriately, the ID operation amplifier can’t operate normally. Please open the inner parts, adjust the trimmer potentiometer, which behine the panel, by metal bottle opener carefully, till the liquid level is shown normal.

The third trouble: A certain or several colour-changeable luminant diodes aren’t light.

Analyse and overhaul: (1)press the fast detecting button, if these colour-changeable luminant diodes can show green, it illustrates that the colout-changeable luminant diodes’ red section no longer gave