Foxboro E69F Converter

In terms of performance indicators, the accuracy of output codes 2 and 3 is ± 1.0% range, and codes 7 and 8 are ± 2% range; Linear typical ± 0.5%, repeatability typical ± 0.25%, hysteresis typical ± 0.5%, dead zone 0.1% range. If the on-site performance shows "output jitter and poor repeatability", first check whether the gas source contains water, whether the nozzle baffle is contaminated, whether the output pipeline is leaking, and then check the coil and feedback components. If it is manifested as "linear difference but adjustable zero range", check whether the valve or actuator load exceeds the converter capacity, whether the output pipeline is too long, and whether the joint is leaking air.

Common Fault Tree

No output or no change in output. First, confirm that the input circuit has 4-20mA or 10-50mA and impedance matching (170 Ω or 27 Ω); Confirm again that the supply pressure has reached the nominal value and is higher than the maximum output of 20kPa; Check if the positive and negative effects are selected incorrectly. If there is input, voltage supply, and output, check the polarity of the electrical wiring, open/short circuit of the coil, and blockage of the air circuit. Explosion proof type - T must be equipped with - J junction box or compliant cable sealing. PG11 ordinary gland cannot be used in situations that require flame isolation.

Output in reverse. Positive and negative effects are chosen to be opposite. If the original valve is "fault closed" during replacement, the new converter may react and cause the valve opening to be reversed. Therefore, the valve must be reselected according to its function and cannot be forcibly changed by adjusting the zero position.

Zero drift. First check the installation tilt and calibration position, then check for supply pressure fluctuations, ambient temperature, and water content in the gas source. The impact of supply pressure may be small, but long-term fluctuations will be superimposed. If the zero position cannot be adjusted, check whether the feedback flexible component is deformed and whether the coil is stuck.

Insufficient output or inability to carry load. Verify the output code and supply voltage. Code 2 has a smaller capacity, code 3/8 is larger, and code 7 is centered. When the supply pressure is lower than the maximum output+20kPa, the output will be "blocked". Air leakage, filter blockage, and inaccurate output meter can also cause misjudgment.

Abnormal increase in gas consumption. Check for leaks in the output pipeline and joints, gaps between nozzle baffles, and water accumulation in the filter pressure reducer. Sudden increase in gas consumption is often not an electrical issue, but rather contamination of the gas path seal or baffle.

Explosion proof area replacement failed. Let's first look at the classification of electrical safety. FM explosion-proof is suitable for Class I Groups C, D Division 1, Class II Groups E, F, G Division 1, temperature Class T6, only E69F-T, classification CS-E/FD-A; FM non ignition is suitable for Class I Groups A, B, C, D Division 2, Class II Group G Division 2, - B, and - T, CS-E/FN-A。 CSA certification for Class I Groups A, B, C, D Division 2- B/- T, CS-E/CN-A; CSA Explosion proof Class I Group D, Class II E, F, G, Class III Division 1- T, CS-E/CD-A. ATEX flame explosion-proof EEx d IIB Zone 1, Ta -40 to+80 ℃, T5 uses - T, CS-E/LD-E, and requires - J overall explosion-proof junction box. For intrinsic safety applications, it is necessary to verify the associated equipment: FM intrinsic safety certification module or Honeywell Class 38 Barrier 38454-0000-0110-113-F5B5, etc., CSA 170/27 Ω coil connected to CSA certified Invensys I/O module, ATEX intrinsic safety EEx ia IIC Zone1/Zone1/- B/- T, CS-E/KA-E; ATEX non ignited EEx nA IIC Zone 2 uses - B/- T, CS-E/KN-A. If the electrical classification code changes during replacement, even if the mechanical interface is the same, it cannot be directly replaced.

Junction boxes, labels, and maintenance details

The shell is made of die cast low copper aluminum alloy body and cover, coated with epoxy powder, meeting IEC IP65 and NEMA Type 4 standards. The data card can accommodate up to 86 characters and spaces for customer tags; If not enough, stainless steel customer labels can be added, with a maximum of 10 lines and 40 characters per line, and an AS code MTS. Micro junction box approximately 64 × 58 × 33mm, IP65/NEMA 4, available in 1/2NPT, M20, PG11 or PG13.5, front/rear wiring, non explosion proof application; 1/2NPT forward is selected as - M, backward is selected as - P, and other connections follow the AS code from MB-A to MB-F. Explosion proof applications should choose - J integral explosion-proof junction box, PG11 horn type connection should be matched with - J, and cannot be used for CS-E/CD-A and CS-E/FD-A. In terms of size, the explosion-proof type has a diameter of about 150mm, allowing 102mm of cover removal space, with a total length of about 290mm; a clearance of 150mm is required for zero adjustment; Gas output 1/4NPT, electrical input 1/2-inch conduit. The weight is 2.3kg, and the installation bracket and pipeline fixation should be able to withstand the tension of cables and air pipes.