Eltra EMI 55 M Magnetic Incremental Kit Encoder, IP 67

A non-contact magnetic kit encoder with up to 10000 ppr and an IP 67 housing

The EMI 55 M is a 55 mm magnetic incremental kit encoder. A magnet actuator is fitted on the motor shaft and the sensor housing reads it without contact, so there is no wear on the sensing side. The datasheet lists suitability for electric motors, the marine industry, iron and steel, textile machines, wood, paper, glass and marble working machines, and general automation and process control.

It delivers a three channel A / B / Z output with resolution programmed from 1 to 10000 ppr, supply up to 30 V DC, an output frequency of up to 800 kHz and a start-up time of 20 ms typical. The bore of the magnet actuator can be 6, 8, 9.52 or 10 mm. Cable or M12 connector output is offered, and the enclosure is rated IP 67 with an operating range of -40 to +100°C for the cable version.

Main characteristics

• Magnetic non-contact technology, no wear
• Three channel output (A / B / Z) up to 10000 ppr
• Supply up to +30 V DC with several electrical interfaces
• Cable or M12 connector output
• Compact dimensions, IP 67 enclosure
• Magnet actuator bore up to 10 mm
• Operating temperature -40 to +100°C

Technical specifications

EMI 55 M ordering code and connections

The datasheet example is EMI 55M 512 Z 5/30 P 10 X X M12 R .162 +XXX.

Installation and operating notes

The magnet actuator must be fitted with the allowable play stated in the datasheet: plus or minus 0.2 mm axially and plus or minus 0.1 mm radially. Mount the actuator on a g6 shaft and set the gap before tightening the housing.

The datasheet gives a magnetic hysteresis, which means the output pulse position shifts slightly when the direction of rotation reverses. At low counts of up to 256 ppr the figure is 0.70 degrees, so choose a higher count when reversing accuracy matters.

With the M12 connector the operating range is limited to -25 to +85°C; the full -40 to +100°C applies to the cable version.

Applications for the EMI 55 M

A kit encoder is practical where a motor has an open shaft end and little space, for example steel and textile machines, paper and glass lines, marine auxiliaries and electric motors that run in dust. The IP 67 housing with no optical disc makes it a contamination-tolerant option.

The 10000 rpm rating and the 800 kHz output frequency suit fast spindles. For hazardous areas use the EX 80 instead; the EMI 55 M datasheet gives no explosion protection marking.

Information to send with an RFQ for the Eltra EMI 55 M

Send the information below to receive a quotation for the EMI 55 M.

• Magnet actuator bore diameter
• Resolution and zero pulse
• Supply voltage and output circuit
• Cable length or M12 connector, and the ambient temperature

Related items and documents

The datasheet photo is shared with the EMA 55 absolute version in the same series. Neighbouring products can be browsed in encoders. A copy of the datasheet is provided. Seven Star LLC deals with EMI 55 M quotation requests after the full code and number of pieces are given.

Commissioning and maintenance notes

Magnetic kit encoders are useful in the region on motors and machines exposed to dust, humidity and vibration, such as marine equipment, irrigation pumps, outdoor machinery and industrial motors, where an optical encoder could be affected by contamination. Before installation, fix the magnet actuator on the shaft and set the air gap between the magnet and the sensor as given in the datasheet, because the gap affects signal quality.

Match the output type, resolution and supply voltage with the drive or counter input. Use shielded cable with the shield earthed as described in the manual, and keep it away from motor power cables. Check the operating temperature against the real conditions near the motor, especially in hot plant rooms or outdoor installations, and inspect the cable, connector and fixing during routine maintenance.

When ordering a replacement, record the resolution, output type, shaft size and magnet type of the existing encoder, so the new unit fits without changes to the drive settings. Keeping one spare sensor and magnet for critical machines shortens downtime.

Related Eltra products: Eltra EH 53 A/B Blind Hollow Shaft Incremental Encoder, Eltra EH 50 FA/FP Through Hollow Shaft Incremental Encoder, Eltra EL 63 Compact Hollow Shaft Incremental Encoder, 35 mm Height, Eltra ER 38 F/G Miniature Blind Hollow Shaft Incremental Encoder, Eltra EX 80 A/D ATEX Explosion-Proof Incremental Encoder and Eltra AAM 36 B CANopen Magnetic Multiturn Absolute Encoder.