Kübler Sendix 7000 ATEX IECEx Incremental Encoder Zone 1

A flameproof incremental encoder for Zone 1 and Zone 21

The Kübler Sendix 7000 is an incremental shaft encoder with Ex protection in a compact 70 mm housing made of seawater-durable aluminum. It carries an ATEX EU type-examination certificate (IBExU 15 ATEX 1091 X) and an IECEx certificate of conformity (IECEx IBE 15.0020 X) for the flameproof-enclosure protection type, for gas (II 2G Ex db IIC) and dust (II 2D Ex tb IIIC) atmospheres. The hollow-shaft sibling is the Sendix 7020.

The encoder offers up to 5000 pulses per revolution with RS422 or push-pull outputs, axial or radial PUR cable outlets, IP67 protection and the same Safety-Lock bearing design as the standard Sendix range. These properties make it a candidate for drives, winches and shaft monitoring in oil and gas, offshore, chemical and marine areas, subject to the area classification and temperature class on site.

Technical specifications

Decoding the 8.7000 order code

The type key is 8.7000.1 b c d.e.f. The flange digit is fixed at 1 (clamping or synchro flange, 70 mm, IP67).

Selection checklist for hazardous areas

Before ordering, compare the zone, gas or dust group, ambient temperature and maximum rotation speed on your site with the certificate: the temperature class depends on the speed (T4 at 6000 rpm, T5 at 2000 rpm for gas). The X in the certificate numbers marks special conditions of use, so the certificate must be read by the installer. Cable gland and cable entry details are part of the installation design and are not covered by this page.

For safe-area machinery use the standard encoders such as the

Kübler Sendix 5000.

Mechanical installation of the Sendix 7000

Most early encoder failures come from the mechanical coupling rather than the electronics. Align the encoder shaft with the driving shaft as closely as practical and use a flexible coupling so that small offsets and axial movement are not passed into the encoder bearings. Check the shaft load figures given above against the real installation, particularly where belts, gears or long overhung shafts are involved. Mount the flange on a rigid bracket that does not resonate at the machine running speed, and avoid hammering any part onto the shaft.

In a hazardous area, the mechanical work also has to respect the Ex design. Do not modify the housing, drill extra holes or change the flameproof joints, and keep the certificate and the special conditions of use with the installation records so that inspectors can compare the equipment with the documentation.

Commissioning checks

Confirm that the type key on the label matches the design documents: output circuit, supply voltage, pulse rate and cable outlet. Before power is applied, check the cable routing and termination in the safe area or approved junction box against the terminal assignment in the attached datasheet. Once powered, turn the machine slowly and confirm in the drive or PLC that counts increase in the expected direction, that the pulse rate setting in the receiving device matches the encoder, and that the speed reading agrees with an independent reference. Run the machine up to its normal maximum speed and confirm that this speed is consistent with the temperature class chosen for the area.

Operating conditions in Oman and GCC hazardous areas

Oil and gas facilities, terminals and chemical plants in Oman and the wider GCC place equipment in strong sun, fine dust and, near the coast, salty humid air. The ambient range on this page ends at +60 °C, and a dark metal housing in direct sun can run hotter than the surrounding air, so consider shading the encoder and measure the surface environment during summer commissioning. Dust layers on equipment in dust-zone areas should be kept under control as part of housekeeping, because a thick layer can affect surface temperature. For offshore and coastal sites, the seawater-durable aluminum housing is a starting point, and the stainless steel option listed above can be discussed where the environment is especially aggressive.

Inspection and maintenance

Include the encoder in the periodic Ex inspection programme required on site. Look for damage to the housing and cable, signs of corrosion, loose mounting bolts and wear in the coupling. Any repair to flameproof equipment should follow the manufacturer instructions and the applicable hazardous-area standards; when in doubt, replace the unit rather than attempting a field repair.

Documents and quotation

The attached datasheet (07/2024 edition) covers the Sendix 7000 and 7020 with the Ex certificates, order codes, technical data, terminal assignment and dimensions. Send the area classification, the pulse rate, shaft, output circuit, supply and cable length when requesting a quotation.