SAFETY INSTRUCTIONS H250 M40 1.1 General notes This additional instruction applies to explosion-protected versions of variable area flowmeters with electrical built-ins with protection type increased safety "e", equipment protection level (EPL) Gc. It completes the standard manual for the non explosion-protected versions.
SAFETY INSTRUCTIONS H250 M40 1.4 Safety instructions If these instructions are not followed, there is a risk of explosion. Assembly, installation, start-up and maintenance may only be performed by personnel trained in explosion protection! CAUTION! The operator or his agent is responsible for observing any additional standards, directives or laws if required due to operating conditions or place of installation.
DEVICE DESCRIPTION H250 M40 2.1 Device description Variable area flowmeters measure and display the volume flow of flammable and non- flammable gases and liquids. Depending on the device version, electrical limit switch contacts ® and a 4...20 mA signal output with HART communication, a Foundation Fieldbus interface or a Profibus PA interface can be installed in the indication unit.
DEVICE DESCRIPTION H250 M40 2.3 Marking The marking of the entire device is on the indication unit, where the following identification plates can be found (refer also to designation code). Figure 2-2: Example of a nameplate 1 Device type 2 Device version 3 Identification number of the notified body ATEX &...
DEVICE DESCRIPTION H250 M40 2.4 Flammable products Atmospheric conditions: Atmospheric conditions: Atmospheric conditions: Atmospheric conditions: The standard atmospheric conditions under which it may be assumed that Ex equipment can be operated are: • Temperature: -20...+60°C / -4...+140°F • Pressure: 80...110 kPa (0.8...1.1 bar) / 11.6...15.9 psi •...
DEVICE DESCRIPTION H250 M40 2.5 Equipment protection level Variable area flowmeters are designed according to IEC 60079-0 and IEC 60079-7 in equipment protection level (EPL) Gc for use in zone 2. The inside of the measuring unit is also approved for zone 2.
DEVICE DESCRIPTION H250 M40 2.7 Ambient temperature / temperature classes Due to the influence of the product temperature, variable area flowmeters with built-in electrical equipment (electric variants) are not assigned to any fixed temperature class. The temperature class of these devices is rather a function of the product temperature and ambient temperature that is present and the specific device version.
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DEVICE DESCRIPTION H250 M40 Using a heat-resistant connecting cable Heating jacket ≤ 40 ≤ 60 ≤ 65 without with HT version DN15, DN25, DN50 DN15, DN25 DN80, DN100 DN50, DN80 Table 2-2: Temperature table in °C 1 Maximum value of the product temperature for the use of a standard connecting cable. For higher product temperatures a connecting cable with a temperature resistance of 90°C is required.
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DEVICE DESCRIPTION H250 M40 Maximum permissible product temperature T [°C] Heating T2, T1 jacket ≤ 40 ≤ 60 ≤ 65 ≤ 60 ≤ 65 ≤ 40 ≤ 60 ≤ 65 ≤ 40 ≤ 60 ≤ 65 with without version [°C]...
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DEVICE DESCRIPTION H250 M40 Maximum permissible product temperature T [°F] Heating T2, T1 jacket ≤ 104 ≤ 140 ≤ 149 ≤ 140 ≤ 149 ≤ 104 ≤ 140 ≤ 149 ≤ 104 ≤ 140 ≤ 149 with without version [°F]...
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DEVICE DESCRIPTION H250 M40 Maximum permissible product temperature T [°C] Heating jacket T4...T1 ≤ 40 ≤ 60 ≤ 65 ≤ 60 ≤ 65 without with HT version T [°C] DN15...DN100 DN15...DN80 with / without ESK4 / ESK4-T ESK4-FF / ESK4-PA not adm.
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DEVICE DESCRIPTION H250 M40 Reference point observation Reference point observation Reference point observation Reference point observation The permissible product and ambient temperatures may be exceeded or undershot as long as the permissible temperature range of the reference point of the display is not exceeded.
INSTALLATION H250 M40 3.1 Mounting Mounting and setup must be carried out according to the applicable installation standards by qualified personnel trained in explosion protection. The information given in the manual and the supplementary instructions must always be observed. Variable area flowmeters must be installed in such a way that •...
INSTALLATION H250 M40 3.2 Special conditions Equipotential bonding Connect the connection parts for the equipotential bonding of the H250 measuring unit and the M40 indicator to the equipotential bonding system of the hazardous area. INFORMATION! The ground terminal on the gate of the cable entry of the display guarantees an electrostatic connection of the device and complies with the requirements of an equipotential bonding connection.
ELECTRICAL CONNECTIONS H250 M40 4.1 General notes The built-in equipment is connected electrically in the indication unit. The connection terminals enable connection to a wire size of 0.25...2.5 mm². The connecting cables should be selected according to the applicable installation standards and the maximum operating temperature.
ELECTRICAL CONNECTIONS H250 M40 4.4 Grounding and equipotential bonding The signal converter shall be connected to the equipotential bonding system of the hazardous area via the internal or external grounding connection on the signal converter housing. The measuring unit and the signal converter are electrically connected via an equipotential bonding connection.
OPERATION H250 M40 5.1 Start-up Start-up is only permitted when the variable area flowmeter: • is correctly installed in the system and connected. • has been checked for the proper state with regard to its installation and connection requirements. • has been properly sealed in the electronic compartment or there is no explosive atmosphere present.
SERVICE H250 M40 6.1 Maintenance Maintenance work of a safety-relevant nature within the meaning of explosion protection may only be carried out by the manufacturer, his authorised representative or under the supervision of authorised inspectors. For systems in hazardous areas, regular tests are required in order to maintain the proper condition.
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NOTES H250 M40 11/2019 - 4007945001 - AD H250-M40 Exec Gc R01 en www.krohne.com...
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• Process Analysis • Services Head Office KROHNE Messtechnik GmbH Ludwig-Krohne-Str. 5 47058 Duisburg (Germany) Tel.: +49 203 301 0 Fax: +49 203 301 10389 info@krohne.com The current list of all KROHNE contacts and addresses can be found at: www.krohne.com...
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