The EMETA encoder will give accurate and reliable angle information if its performance and its environment are given consideration.

The out put signal consists of two pulse trains offset 90°EL, where one full pulse is 360°EL. Since the two pulse trains are offset it is possible to detect direction of rotation. If the signal on channel A goes high before channel B the shaft turns in one direction and if B goes high before A rotation is opposite. Signal high correspond to supply voltage and voltage low to zero voltage
Most encoder models have an additional signal once per revolution called marker or reference to be used as a check on count or a home for some special function. In order to a precise signal the marker is gated with signal A and B so that when both A and B are high the marker is high.

The number of pulses in one shaft revolution, the encoder resolution, is dependent on the number of lines on the code disc, for instance 500 lines will give 500 pulses. The number of lines on the disc is almost a free choice up to the max, bearing in mind that a non-standard rate will require longer delivery time than standard rates.
If receiving electronics is set up for reading all shifts between high and low level it can detect 4 changes in one pulse. The resolution of the set up will then have increased four-fold, in our example from 500 to 2000.

Encoder accuracy is given in °EL as the deviation of one pulse to its nominal place measured from one pulse to any other on either channel. This deviation is non-cumulative that is it always back to zero after a full turn.

Channel separation is the deviation from the 90°EL offset between channels and is measured from one channel to the other.

Signal frequency is the rate with which the pulses are sent out from the encoder and is dependent of number of lines on the disc and how fast the shaft and disc is turned. It is measured in signals per second. Remember that attempting good resolution at high speed will give a high signal frequency that must be accepted by the receiving electronics. A PLC has perhaps a max of 7kHz.

Mechanical
Give the encoder best possible protection remembering that it is a precision instrument. Consult the datasheet for the chosen encoder for environment protection. IP65 is the most frequent protection i.e. spray water and dust proof.
The internals of the encoder will withstand high rates of shocks and vibration. The outside should be protected against abuse. Use no hammers or prying tools and protect it from falling objects or being run into.
The shaft-load must be limited even though double bearings are used. The encoder size limits the bearing size and hence load carrying capacity is also limited. Overloading the bearings will reduce their life fast. At rated load bearing life is 50,000 hours. If load is increased from 5 to 50 kg the bearing life will be reduced to 50 hours, as universal bearing load formula shows that life is reversed proportional in the third power.
Use a flexible coupling when connecting the encoder shaft. For low resolution a rubber house or a coil spring might do as a flexible connection, but the higher the resolution the lager requirements there is on the coupling. A bellows coupling might seem expensive but it prevents the driving shaft's axial and radial loads to be transmitted to the encoder bearings with correspondent life shortening.

Electrical
Connecting the encoder
Start by checking supply voltage and compare to rated voltage on the labile. Also check connection layout in the adjoining encoder document to secure correct signal and voltage to the correct place. Most of EMETA encoders are 100% connection proof but they will not withstand 230V AC.
If long supply and signal cables are used a voltage drop will occur in the supply lines, not only will the +V decrease the 0 voltage is going to lift from 0V decreasing the voltage span. This is important especially when the voltage supply is 5V since a 1 V loss due to cable resistance will give an operating voltage span of only 3V that might become critical. The logical "0" will also be endangered.
EMETA encoders are CE approved and will not be disturbed by industrial noise nor will they create noise that could harm other electronic equipment. Even so, it is good practice not to locate signal cables on the same shelves as power cables. Do not place signal cables in the vicinity of machines with intense state of noise such as welding equipment.
Screens
Use screen cable when connecting the encoder. Encoders with cable connection have the screen connected to the encoder chassis. To obtain largest possible protection from the screen it is sound practice to connect it indirectly in the receiving electronic earth with a 10nF/3000V capacitor giving both LF and HF protection. Additional protection is achieved through pair-twisted cable using the pair for signal and inverted signal.
Signals
Many of the EMETA encoders have both signal and inverted signal output corresponding to RS422. This arrangement is called line driver and it is used for two reasons. When the signal and the inverted signal is used and the cables are connected to each other with a 100ohm resistance before being connected to the line receiver in the encoder module of a PLC or computer the module detect the voltage difference between the two signals. A disturbance will not affect such an arrangement as it creates the same spike on both lines the difference between them remains essentially unchanged. The second advantage with line driver/receiver is the signal can be transmitted over long lines, up to 1000 m.

SCHEMATIC DISTURBANCE
As signal is detected as difference between signal and inverted signal in a line driver set-up a disturbance will not create a switch in signal in the receiving end.