MTL700, LB800, LB900, S2000 series Zener barrier
Promulgator
：admin Time：2018-08-22
I. Overview
◆MTL700, LB800, LB900, S2000 series Zener safety barrier is a new safety barrier series product of our company. The product is in accordance with the relevant provisions of GB3836.4-2000 [intrinsic safety type "i" for explosion-proof electrical equipment for explosive gas environment]. Manufacturing production. It has passed the explosion-proof test of the National Explosion-proof Quality Supervision and Inspection Center and obtained the certificate of explosion-proof qualification.
◆ LB900 series Zener safety barrier, can be used with a variety of on-site instrument such as transmitter (digital communication smart transmitter, 4-20mA analog signal ordinary transmitter, domestic DDZ-III transmitter), Electrical converters, electric valve positioners, various types of thermocouples, thermal resistances, switches (contacts and analog switches), flow meters (turbine, waist, scraper, vortex flow transmitters, etc.), solenoid valves and various The special instrument constitutes an intrinsically safe explosion-proof system for the automatic process control of modern industry, and is widely used in petroleum, chemical, pharmaceutical, ship and other fields. Reliable equipment that limits hazardous energy into an explosive atmosphere.
◆The use of the S2000 series Zener safety barrier is the same as that of the LB900 series. Its characteristic is that the terminal resistance of the safety barrier is reduced, and the range of safety barriers for the design department and users is widened.
Second, the safety barrier and the primary instrument supporting requirements
1. The selected safety barrier and primary instrument should obtain the explosion-proof certificate issued by the national explosion-proof inspection department, and can be formed into an intrinsically safe explosion-proof system after being confirmed by the explosion-proof inspection unit.
2. Cables and primary instruments are energy storage devices, which must be calculated according to the explosion-proof parameters of the safety barrier. (This condition does not take into account the power supply).
The basic combination conditions of the intrinsically safe explosion-proof system are:
Uo≤Ui
Io≤li
Co≥Ci+Co
Lo≥Li+Lo
Where: Uo maximum output voltage
Io maximum output current
Co maximum load capacitance
Lo maximum load inductance
Ui primary instrument allows the highest input voltage
Li maximum input current allowed by the meter
Ci maximum internal equivalent capacitance of the instrument
Li primary instrument maximum internal equivalent inductance
The maximum distributed capacitance allowed by the Cp connection wire (or cable)
The maximum distributed inductance allowed by the Lp connection wire (or cable)
3. According to the national standards, the intrinsic safety level is limited to:
Class IIC: 20 μJ
Class IIB: 60 μJ
When the intrinsic safety limit level of the instrument and the safety barrier is different, the combination of the explosion-proof system can only be degraded.
Third, technical specifications and main parameters
a) Explosion-proof mark: [Ex(ia)]IIC, [Ex(ib)]IIC, [Ex(ib)]IIB
b) Installation location: safe area
c) Installation method: DlN standard rail (35mm) installation or guide bar busbar installation; M4 bolt spacing 11.5mm
d) Maximum allowable voltage: 250VAC/DC
e) Environmental conditions: continuous use temperature -10 ° C ~ +45 ° C; storage temperature -40 ° C ~ +80 ° C; relative humidity 5 ~ 95% RH
Fourth, installation and grounding
A) Installation method: two installation methods
1) Install the DlN standard rail (35mm) and directly attach the safety barrier to the DlN rail.
2) Guide strip installation
a) On a 20mm wide copper row, drill two mounting holes with a pitch of 11.5 mm and a hole diameter of ø4.5 mm. Insert the two grounding bolts of the safety barrier into the screw and reliably ground the copper bar.
b) Installation location: a safe place with no corrosive gas and no strong vibration.
c) terminal block serial number
Non-intrinsically safe terminals: 1, 2 intrinsically safe terminals: 3, 4
d) The grounding resistance of terminals 5 and 6 should be no more than 4 Ω, and the grounding wire resistance should be no more than 1 Ω.
Five, matters needing attention
a) The safety barrier should be installed in a non-hazardous area.
b) The wiring between the intrinsically safe end and the non-intrinsically safe end of the safety barrier must not be connected incorrectly, and the wires should be laid separately.
c) It is forbidden to directly test the insulation between the safety gate terminals with a megger. If you check the system wiring, you must disconnect all safety barrier wiring.
d) Once the safety barrier is damaged, the user shall not repair it himself and shall replace it.
e) It is forbidden to use the ground wire of the Zener barrier to perform strong electric operation such as electric welding, so as to avoid a large number of Zener safety barriers being burned at the same time.
f) When using the secondary instrument, it must be confirmed that the working voltage of all secondary instruments connected to the safety barrier or the maximum voltage that may be generated inside it does not exceed
The maximum allowable voltage of the safety barrier is 250VDC/AC.
g) When the system is connected (no dangerous gas on site), all the wiring of the safety barrier should be disconnected. After confirming that the system is successfully debugged, connect the safety barrier wiring and put it into use.
h) Be sure to pay attention to the wiring method of the intrinsically safe circuit and the restrictions on the connecting wires:
1) Intrinsically safe lines and non-intrinsically safe lines shall be laid separately in the sink and protection tubes;
2) The intrinsically safe wire is blue;
3) The insulation strength of the connecting wires should be greater than 500V;
4) Thermocouple lead application compensation wire;
i) In addition to complying with this manual, the installation and maintenance of the safety barrier must also strictly abide by the relevant provisions of GB3836.15—2000 “Electrical Equipment for Explosive Gas Environments, Part 15: Electrical Installation of Hazardous Locations (Except Coal Mines)”.
Note: Once the Zener barrier is damaged, the user must not repair the reuse and should be replaced.
