Outline
Base plate mounted isolated safety barrier PHC-11HF-34 can convert the safety zone contact switch, logic level input into intrinsically safe equipment drive quantity, output to the hazardous area site, so as to control solenoid valves, acoustic and visual alarms and so on. Signal status indicator set red and yellow dual-color, alarm display red, output solenoid valve and other work display yellow.
The product needs independent power supply, power supply, input and output are isolated at three ends.
Main technical parameters
| Number of channels: | one input and one output |
| Safety side input: | |
| Input signal: | contact control DC voltage |
| Hazardous side output: | |
| Output signal: | 22V~24V DC, UE/IE=12.8V/48mA |
| Allowable inversion function: | K1 is set to ON side, circuit output inverted |
| LED indicator: | yellow—output relay is in normal operating state |
| Alarm relay function: | Set the dip switch K2 to "ON" side, the circuit selects the alarm function. Load resistance <50Ω, short-circuit alarm (SC); load resistance >10kΩ, open circuit alarm (LB) |
| Alarm relay characteristics: | Response time: 20ms Driving capacity: 250V AC/2A, 30V DC/2A resistive loads Load type: resistive load |
| Output accuracy: | 0.1%F.S (typical: 0.05%F.S) |
| Response time: | 20ms to 90% of final value |
| Temperature parameters: | operating temperature -20℃~+60℃; storage temperature -40℃~+80℃ |
| Air relative humidity: | 10%~95%RH without condensation |
| Insulation strength: | intrinsically safe end and non-intrinsically safe end (≥3000V AC/min) |
| Insulation resistance: | ≥100MΩ (input/output/power supply between) |
| Electromagnetic compatibility: | in line with IEC 61326-1 (GB/T 18268), IEC 61326-3-1 |
| Mean time to failure: | 100000 hours |
| Wire requirements: | cross-section ≥ 0.5mm2; insulation strength ≥ 500V |
| Applicable field devices: | audible and visual alarms, intrinsically safe solenoid valves |
| Installation site: | installed in the safe zone, can be connected with the highest in Zone 0, IIC, Zone 20, IIIC hazardous locations of the intrinsically safe instrumentation |
| Safety certification | |
| Certification body: | National Explosion-proof Electrical Product Quality Supervision and Testing Center CQST |
| Certification standard: | GB/T 3836.1-2021, GB/T 3836.4-2021 |
| Explosion-proof symbol: | [Exia Ga]ⅡC, [Exia Da]ⅢC |
| Certified parameters (between terminals 1-2): | Um: 250V AC/DC, Uo=25.2V DC, Io=147mA, Po=0.92W, Co=0.107μF, Lo=1.5mH. |
| Terminals | Terminal function definition | |
| 1 | Output- | 12.8V/48mA |
| 2 | Output+ | |
| 7 | Output alarm | Alarm relay |
| 8 | Output alarm | |
| 10 | Input+ | Contact control DC voltage |
| 11 | Input- | |
Wiring
1. Meter wiring adopts removable spring-type terminals, easy to use. The upper end of the instrument is intrinsically safe (blue plug), which leads to the signal terminal of the hazardous side; the lower end of the instrument is non-intrinsically safe, which is directly plugged into the base plate, and is supplied with power uniformly through the sockets and wiring on the base plate and leads to the signal terminal of the safe side;
2. Intrinsically safe side of the wiring should be selected with blue marking intrinsically safe wire, wire soft copper cross-sectional area must be greater than 0.5mm², insulation strength should be greater than 500V;
3. Isolated safety fence intrinsically safe side and non-intrinsically safe side of the wiring conductor in the sink should be laid separately, each using a protective sleeve;
4. The bare length of the wire is about 10mm, if the soft line also need to install metal size >10mm cold pressure head, hard line is not required. The wire can be directly inserted into the wiring hole without a screwdriver.
Installation
Isolated safety barriers should be installed in a safe place, and also comply with
GB3836.13-2013: "Explosive atmospheres—Part 13: Equipment repair, overhaul and reclamation"，
GB/T3836.15-2017: "Explosive atmospheres—Part 15: Electrical installations design ,selection and erection", GBT3836.16-2017: "Explosive atmospheres―Part 16: Electrical installations inspection and maintenance", GB/T3836.18-2017: "Explosive atmospheres—Part 18: Intrinsically safe electrical systems", GB15577-2018: "Safety regulations for dust explosion prevention and protection",
and GB50257-2014: "Code for construction and acceptance of electric equipment on fire and explosion hazard electrical equipment installation engineering".
Isolated safety grille adopts the bottom plate mounting method. The operation steps are as follows:
Disassembly
1. Pull out the instrument from the socket of the base plate upwards as follows:
2. When separating the wires on the terminals, please insert a standard screwdriver into the groove of the orange operation position and push it inward, then pull the wires out of the wiring hole.
Maintenance
1. Before power-on commissioning, you must check again whether the model and explosion-proof grade of the isolated safety barrier is consistent with the design and use of the environment, whether the wiring between the safety side and the hazardous side is correct, and whether the polarity of the power supply and signal is correct;
2. Strictly forbidden to use megohmmeter to test the insulation between the terminals of the isolated safety barrier. If you want to check the insulation of the system line, you should first disconnect all the isolated safety barrier wiring, otherwise it will cause the internal fast fuse blown;
3. Products are strictly inspected and quality controlled before shipment, if you find use of abnormalities, please contact your nearest agent or call the technical support hotline;
4. Six years from the date of shipment, the product in the course of normal use of the quality problems arising from us free of charge to solve.
Intrinsically safe explosion-proof circuit system
Isolated safety barriers and field intrinsically safe instrumentation connected to form an intrinsically safe explosion-proof circuit (intrinsically safe circuit) system must be confirmed before use:
1. The explosion-proof grade of the field intrinsically safe instrument should be in line with the use of the environment, and it should be the instrument which has been certified by the state-authorized explosion-proof product certification body and has obtained the explosion-proof certificate of conformity.
2. Isolated safety barriers and on-site intrinsically safe instrumentation between the respective certification parameters are clear, and in line with GB/T 3836.15-2017, such as the requirements of the 12th 12.2.5.
3. If any of these parameters are unclear and need to constitute an intrinsically safe circuit system, they must be confirmed by a state-authorized explosion-proof product certification body.
Precautions for use of isolated safety barriers
Maximum external capacitance (Co) and inductance (Lo) values are used with attention to the following requirements:
1. For circuits containing only distributed inductance and capacitance, such as the distributed capacitance and inductance of the cable, the maximum permissible external capacitance and inductance values for the permissible values of Co, Lo in the certification parameters.
2. For the circuit combined with cable, when the intrinsically safe circuit contains inductance or capacitance with a maximum of 1% or less of the permissible value in the certification parameters, the maximum permissible external capacitance and inductance value is the permissible value of Co and Lo in the certification parameters.
3. For inductive and capacitive combined circuit, when the inductance and capacitance are greater than the certification parameters in the Co, Lo 1% of the permissible value (excluding cables), the maximum permissible external capacitance and inductance values for the certification parameters in the Co, Lo 50% of the permissible value.
4. For the qualified products that have passed the explosion-proof inspection, it is not allowed to replace the components or change its structure, so as not to affect the explosion-proof performance.