SZM-20 RPM meter

SZM-20 magnetic tachometer is composed of two parts – an indicator and a sensor, which are connected together through a transmission cable without any external power supplied, able to remotely measure the rotational speed of a variety of power equipment.
◆ Working Principle
The sensor is mainly composed of a permanent magnet and an induction coil. The permanent magnet is coupled with a power equipment item through a flexible shaft. When the permanent magnet is rotated by the power equipment, the induced current is generated in the coil, which then is transmitted to the indicator via the transmission cable. Such fluctuating current, after rectified with its voltage reduced, is used to drive the wide angle ammeter for indicating the measured rotational speed.
◆ Technical Conditions
1.      Precision Grade:   1.5 (at 20±2°C)
2.      Working Environment:  Temperature range from -25°C to +55°C.
Relative Humidity 5% -100%, inclusive of frosting
3.       Humidity Added Error:  An additional error is less than 1.2% of the upper limit of  the measured value with every 10°C of temperature change.
4.       Measurement Range: (0-1500) r/min speed ratio1:1;
(0-2000) r/min speed ratio1:1;
(0-3000) r/min speed ratio1:2;
5.      Mechanical Force Tolerance: the meter can withstand the acceleration speed at 100m/S2 and 1000 continuous impacts of vibration in transport at the frequency 60100 times per minute.
◆ Operating Instructions:
1.Time for use: Able to be operated continuously without lubricant oil added.
2.The sensor shall be used together with the indicator completing with it.
3.The resistance of the transmission cable shall not be greater than1.2 ohms, which are equivalent to the wire in the specification of RVV2*l6*0.15 used for a transmission distance of 10m. An additional 0.2% error will result for each 10m of distance if the said wire is used.
◆ Weight:
Sensor: 330g
Indicator: 590g
◆ Installation Dimensions:
1.      Indicator
Profile dimensions: Ф108x85
Hole cutting size: Ф98
2.      Sensor
Please specify the model when ordering: SZM-20A, SZM-20B, SZM-20C, SZM-20D
◆ Accessories
Accompanying transmission cable:  1
Certificate of Conformity:  1