Temperature and humidity sensor how to choose the model

2019-03-23 08:49:45

Temperature and humidity sensor how to choose the model? Temperature and humidity need to pay attention to the measurement range, accuracy of measurement, and drift and temperature drift when purchasing.

1. Select measurement range

Just like the measurement of weight and temperature, selecting the humidity sensor first determines the measurement range. In addition to the meteorological and scientific research departments, the measurement of temperature and humidity generally does not require full wet-range (0-100% RH) measurements.

2. Select measurement accuracy

The measurement accuracy is the most important indicator of the humidity sensor. For each increase of -1%, it is the previous step or even the previous level for the humidity sensor. Because to achieve different accuracy, the manufacturing costs vary greatly, and the price difference is very far. Therefore, users must tailor their clothing to avoid blindly pursuing â€œhigh, refined, and sharpâ€. If the humidity sensor is used at different temperatures, the indication must also consider the effect of temperature drift. It is well-known that relative humidity is a function of temperature and that the temperature affects the relative humidity in a given space. Each temperature changes by 0.1Â°C. A humidity change (error) of 0.5% RH will be generated. If it is difficult to use a constant temperature in the occasion of use, it is not suitable to propose excessively high humidity measurement accuracy. In most cases, the accuracy of Â±5% RH is sufficient if there is no accurate temperature control method or if the space under test is unsealed. For those applications that require precise control of constant temperature, humidity, or humidity, or need to track and record changes in humidity at any time, use a humidity sensor with an accuracy of Â±3% RH or more. Accuracy higher than Â±2% RH is not even a standard humidity generator for calibration sensors, let alone the sensor itself. Relative humidity measuring instruments, even at 20-25 Â°C, to achieve 2% RH accuracy is still very difficult. The characteristics given in the general product literature are measured at room temperature (20 Â°C Â± 10 Â°C) and clean gas.

3. Consider drift and temperature drift

In actual use, due to the influence of dust, oil, and harmful gases, the electronic humidity transmitter will age and the accuracy will decrease due to a long use time. The annual drift of the electronic humidity transmitter is generally about Â±2%, and even more. high. Under normal circumstances, the manufacturer will indicate that the effective use time for one calibration is 1 year or 2 years, and it needs to be recalibrated upon expiration.

4. Other considerations

Humidity sensors are non-hermetic. To protect the accuracy and stability of measurements, they should be avoided in acidic, alkaline, and organic solvent-containing atmospheres. Also avoid using in dusty environments. In order to correctly reflect the humidity of the space to be measured, it is also necessary to avoid placing the sensor too close to the wall or in a corner where air does not flow. If the room being measured is too large, multiple sensors should be placed. Some humidity sensors require a relatively high power supply, otherwise it will affect the measurement accuracy. Or the sensors can interfere with each other and they can't even work. When used, provide suitable power supply that meets the accuracy requirements according to technical requirements. When the sensor needs to carry out long-distance signal transmission, it is necessary to pay attention to signal attenuation. When the transmission distance exceeds 200m, it is recommended to use the humidity sensor of the frequency output signal.

In addition, there are some selection criteria. Due to different temperature and humidity measurement principles, temperature and humidity instruments are various. When selecting, users must consider the actual application environment and requirements of users, such as range, output and display, and installation methods. Sampling methods, gas types, materials and structures, control monitoring requirements, environmental hazards, etc. In addition, factors such as cost-effectiveness and maintenance workload should also be considered:

Cost-effective: When using temperature and humidity instruments, you can't just consider the price is low, you should choose the price and performance. This includes price, life, maintenance, and calibration costs. Verification: The method of verification and whether it is easy to consider, even if you do not need high-precision results. It will save you the workload of checking a convenient instrument on site and in situ.

Main use;

V series vertical Machining Center is a medium machine with high rigidity

,high precision,high speed,high efficiency and big torque.Sutiable for manufacturing industries of automobile,motorcycle,aviation & aerspace,instruments,electric appliances,electronics,mould & die,and machine manufacturing etc.And the machine suits for maching valves,cams,moulds,plates,diskd and cases etc.It used not only small or medium production,but also for batch production when integrated into production line.

Function characteristics

1. Wide and special designed guide way

2. Large process

3. High speed and rigidity spindle

4. Special technology for hardening of guide ways ,spindle taper hole

and worktable is applied .So as to insure rigidity and precision stability.

high-rigidstructure,good manufacturing

Application of computer Aided Design(CAD)system to complete the structural design of the optimal.

Machine guides,spindle taper hole hardening,work table,etc.quenching proprietary technology,to ensure the accuracy of the hardness and stability.

Pieces of machine tools based on the use of special casting,high-rigid structure,rail grinding hardening.With its matching plastic rail paste,automatic intermittent run

Cutting machine with a strong ,rigid tapping,high-volume cooling,chip wide trough.

Main drive system

Spindle drive AC servo motor-driven,high-speed,high torque,constant power wide area,low temperature rise,low-nise.

Spindle box for high-rigid structure,with a small thermal deformation,high-precision spindle with a long service life characteristics

Feed drive system

3-axis feed using AC servo motors and precision ball screws,ball screw bearings dedicated support to carry out pretension

Machine main supplier :
Sevro motor:FANUC(japan)
Spindle bearings NSK (JAPAN) SKF(SWIDE)
Pneumatic component: SMC(JAPAN)
Control system:FANUC(JAPAN)
rail grinding ; SHAMBAN(AMERICA)

CNC system:
Operational panel accord with safe regulations,rotary design with easy operation.Sapiential indicator light,showing machine state,easy usage

Maintenance separate hand wheel,convenient machine adjustment FANUC,MITSUBISHI,SIEMENS ETC famous brand CNC system configuratior

Vetical Machining center can into Line Rail Center Machine And Hard Rail center machine

MAIN MODEL AND SPEC

1. Vertical Machining center-Line Rail Center Machine

ITEM	UNIT	V650L	V850L	TH5656L	V1060L	V1270L
CAPACITY
X axis travel	mm	600	800	1200	1010	1200
Y axis travel	mm	420	500	600	600	700
Z axis travel	mm	500	600	710	650	650
Distance from spindle nose to table surface	mm	80-580	150-750	190-900	150-800	110-750
Distance from spindle nose to column surface	mm	550	620	650	660	760
WORKTABLE
Table size (LXW)	mm	800x420	1050x500	1500x780	1300x600	1400x700
Max table load weight	kg	500	500	1200	1000	1100
T-solt size	mm	3-18x110	5-18x805-	5-18x125	5-18x120	5-18x120
SPINDLE
Spindle speeds	rpm	8000	8000	4000	8000	7000
Spindle specifications (installation dia)	mm	BT40/120	BT40/150	BT50	BT40/150	BT40/150
Motor power of spindle	kw	7.5/11	7.5/11	11/15	7.5/11	11/15
FEED SYSTEM
Rapid traverse X,Y/Z	m/min	24	24	24/15	24	24
Max cutting feedrate	m/min	12	12	10	12	12
A.T.C.
Tool storage capacity(Drum/Arm opt)		20/24	20/24	24	20/24	20/24
The larges diameter cutter knife/length	mm	80/300	80/300	110/300	80/300	110/300
Tool change time(T-T)	sec	5/2.5	5/2.5	3	5/2.5	2.5
PRECISION
Positional accuracy	mm	0.01	0.01	0.015	0.01	0.01
Repeatability	mm	0.006	0.006	0.010	0.006	0.006
MACHINE SPECIFICATIONS
Height of machine (H)	cm	250	260	354	265	265
Floor space(LXW)	cm	2330X220	270X235	350X300	320X270	350X270
Total Machine weight	T	4/5	5/6	11/12	7/8	8/9

2.Vertical Machining center-Hard Rail Center Machine

ITEM	UNIT	V650	V850	V855	V1060
CAPACITY
X axis travel	mm	600	800	850	1010
Y axis travel	mm	420	500	550	600
Z axis travel	mm	500	600	600	650
Distance from spindle nose to table surface	mm	150-650	150-750	150-750	130-780
Distance from spindle nose to column surface	mm	530	620	620	665
WORKTABLE
Table size (LXW)	mm	800x420	1050x500	1050x520	1300x600
Max table load weight	kg	500	650	700	1000
T-solt size	mm	3-18x125	5-18x100-	5-18x100	5-18x120
SPINDLE
Spindle speeds	rpm	8000	8000	8000	8000
Spindle specifications (installation dia)	mm	BT40/120	BT40/150	BT40/150	BT40/150
Motor power of spindle	kw	5.5/7.5	7.5/11	7.5/11	7.5/11
FEED SYSTEM
Rapid traverse X,Y/Z	m/min	15	15	15	15
Max cutting feedrate	m/min	10	10	10	10
A.T.C.
Tool storage capacity(Drum/Arm opt)		20/24	20/24	20/24	20/24
The larges diameter cutter knife/length	mm	80/300	80/300	800/300	80/300
Tool change time(T-T)	sec	5/2.5	5/2.5	5/2.5	5/2.5
PRECISION
Positional accuracy	mm	0.01	0.01	0.01	0.012
Repeatability	mm	0.006	0.006	0.006	0.007
MACHINE SPECIFICATIONS
Height of machine (H)	cm	250	260	270	270
Floor space(LXW)	cm	2330X220	270X235	350X300	320X270
Total Machine weight	T	4/5	5.2/6.5	6/7	8/9

Vertical Machining Center

NingXia DaHe Machine Tool (Group) Imp And Exp Co.,Ltd , http://www.nxdhjcmachine.com