Maintenance and troubleshooting of ENOTEC SILOTEC 8000 silo analyzer

Status messages and troubleshooting

The system error relay operates when there is a hardware error, thermocouple open circuit, O2 temperature not reached, temperature too low/too high, O2 sensor open circuit, calibration failure, low/high test gas flow rate, low/high offset, low/high slope, unstable signal, COe board communication error, COe heater short circuit/open circuit, COe sensor open circuit, COe board hardware error, COe calibration failure, invalid factor, remote module error, or sample gas flow rate error. The O2 signal output usually drops to 2.00mA, and the COe related error output is 20.80mA, unless otherwise set.

Common fault one: O2 display fluctuates greatly. Possible reasons include intermittent wiring and poor mV contact inside the probe. Solution: Check the wiring, eliminate looseness and disconnection. Common fault 2: O2 display stops at the end of the range or is too high. Possible reasons may be leakage in the sealing of the measuring probe or O2 sensor flange, or the probe flange not being air tightly welded. Solution: Check all flanges and threaded connections, replace O2 sensors or gaskets, and tighten flange bolts according to torque. Common fault three: Local display is correct but output is incorrect. Check the range setting, measure the mA output of the terminal, and determine if the electronic unit is faulty. Common fault four: O2 displays 0% but the expected process is high. Check the heater resistance (approximately 37.5-47.5 Ω), thermocouple resistance (approximately 2-80 Ω), heating fuse, cable short circuit or open circuit, probe core contact, and whether the measuring cell is damaged. If there is combustible gas present, it may form a reducing atmosphere and reduce the oxygen content on the sensor surface. At this time, it is necessary to be alert to the risk of explosion. Common fault five: high O2 and low COe. Usually, it is due to poor sealing at the coupling point of the COe sensor, causing ambient air to enter the installation pipe. Solution: Tighten or replace the COe sensor coupling component and recalibrate. Common fault six: No COe measurement value, displaying arrow. Possible beyond physical range or COe sensor malfunction. Perform O2+COe sensor inspection and check electrical connections. Common fault seven: No O2 measurement value, empty bar graph. The O2 value may exceed the coverage range of the electronic unit, such as under low O2 and high COe conditions. Perform O2+COe sensor inspection.

Quick check of technical specifications

Electronic Unit SME-53: Steel Powder Coated Shell, RAL6029， Optional GRP or stainless steel 19 inch rack. IP66， 19 inch rack IP20. LCD 240 × 64 LED backlight, thin film keyboard. The O2 range can be configured in two sections, from 0-2% to 0-25% O2, with an accuracy of less than 0.5% of the measured value or 0.02 Vol% O2. The COe range is 0-5000 ppm. Power supply 230V AC ± 10% or 115V AC ± 10%, 50/60Hz. Power consumption heating stage 425VA, measurement mode 225VA. Output O2 and COe are both 0/4-20mA active, maximum load 500 Ω, galactic isolated. Relay 24V AC/DC 1A, solenoid valve relay 230V AC/DC 1A. Size 300 × 440 × 240mm, weight approximately 19kg. Operating temperature -20 ° C to+55 ° C, storage -40 ° C to+80 ° C.

Probe SIL-KES-0001: Process temperature up to 100 ° C, immersion depth of approximately 500mm, process pressure ranging from ± 50mbar to atmospheric pressure. Environmental temperature -20 ° C to+55 ° C. Reaction time<1s, T90<5s. Material SS316, GRP transmitter housing, IP65， Applicable to Zone 22. The power is provided by the electronic unit.

Gas supply: Instrument air according to ISO 8573-1 Class 2, particle size ≤ 1 μ m, oil content ≤ 0.1mg/m ³, dew point pressure -20 ° C, inlet pressure 4-8 bar, O2 content 20.95%. Test gas 1 is instrument air or synthetic air. Test gas 2 according to the test certificate, with a maximum inlet pressure of 3bar and a flow rate of 40-80 l/h.