Product Specification

Zhong he SDJ-501 Shaft Vibration Protection Transmitter for Rotating Machinery

Measured parameter:
  Real-time rotational speed.

Unit type:
  Rotating machinery with various sliding bearings, such as steam turbines, fans, compressors, motors, pumps, etc.

Installation requirements:
  ● For units with existing eddy current probe systems, simply connect the wiring and set the alarm point.

Output interface:

  ●Features 4-20mA output terminals (4-20mA "+" and "-").

  ● On-site LED displays show the machine's operating status (instrument working status OK, alarm, interlock Danger, disconnection BREAK).

  ● Isolated two-stage alarm relay output terminals SPDT (“ALERT” and “DANGER” normally closed or normally open output terminals)

  ● Vibration values ​​can be displayed on-site (connected to QBJ-3Q) and via PLC or DCS.

  ● The buffered output of the original signal is directly connected to the status monitoring instrument (“BUF OUT” output terminal).

  ● Power supply: 24VDC, 220VAC, or 110VAC. For 220VAC or 110VAC options, a separate DC +24V converter power supply is required for isolated power supply.

Continuous speed monitoring system:

    The SDJ-501 is a single-channel speed monitoring and protection transmitter, primarily used for online real-time measurement of the rotor speed of rotating machinery. It outputs the speed value and simultaneously outputs two levels of alarms. This allows for early detection and protection of rotating machinery, extending machine life and reducing unit maintenance. The low-frequency option of the SDJ-501 can measure the zero speed of steam turbines, etc. It is simple and convenient to install, requires no adjustments, and offers a high performance-to-price ratio.

    The SDJ-501 speed transmitter is suitable for speed monitoring of any rotating machinery. The SDJ-501 is easy to install, either in the field or in a control room. For the measurement point, we generally require a groove to be engraved on the shaft to install the probe. Then connect the SDJ-501 transmitter. The groove should be at least 2.5cm deep and 7mm wide.

    The SDJ-501 protection transmitter has all parameters pre-adjusted and calibrated before leaving the factory. Simply connect the corresponding cables; generally, no further adjustments or calibrations are required. However, the SDJ-501 also offers complete adjustment functions, including adjustable parameters such as two-stage alarm points, output zero point, and full-scale calibration. By opening the SDJ-501 protection transmitter's nameplate, you can adjust the two-stage alarm point settings, the 4-20mA output zero point "ZERO," and calibrate the instrument's full-scale range. With its multi-channel protection transmitter functionality and flexible options, the SDJ-501 protector can be tailored to your specific needs.

    The SDJ-501 protection transmitter can be customized to meet various field requirements, with its functions selected according to the ordering options. The SDJ-501 protection transmitter outputs a total speed value of 4-20mA, features two-stage alarms, buffered output of the original signal, and alarm reset (“RESET”). Different full-scale ranges are available for selecting the total speed value, and a low-frequency option is also provided for measuring the zero speed of a steam turbine.

    The 4-20mA output is active and can drive loads up to 750Ω, meaning three or more loads can be connected in series with each load at the output terminal. The SDJ-501 is a 3-wire protection transmitter. For this transmitter, note that the system requires single-point grounding; that is, the negative terminal of the 4-20mA output and the negative terminal of the power supply must share the same "system ground" (COM). The relay output is a fully isolated dry contact output. The relay is an SPDT single-pole double-throw type, which can be connected to normally closed or normally open terminals. The maximum relay load is 2A. It can be directly connected to any PLC or DCS, and can also control alarms, relays, etc.