Motrona MM 640, Operating Instructions Manual

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MM64003a_e.doc / Feb-09 Page 7 / 44
2.1. Power Supply
The MM640 monitor accepts both, a 17 – 40 volts DC power or a 24 volts AC power for supply
via terminals 17 and 1. The current consumption depends on the level of the input voltage and
some internal conditions; therefore it can vary in a range from 100 – 200 mA (aux. currents
taken from the unit for encoder supply not included).
2.2. Auxiliary Outputs for Encoder Supply
Terminals 2 and 18 provide an auxiliary output with approx. +5.2 volts DC (300 mA totally).
Terminals 3 and 19 provide an auxiliary output with approx. +24 volts DC (240 mA totally)
2.3. Impulse Inputs for Incremental Encoders
All input characteristics of the impulse inputs can be set by the parameter menu, for each of
the encoders separately. Depending on the application the unit can accept single channel
information (input A only) or quadrature information (A / B, 90°). The following settings are
possible:
•
Symmetric input (differential) according to RS422 standard
•
TTL inputs at a level of 3.0 to 5 volts (differential, with inverted signal)
•
TTL inputs at a level of 3.0 to 5 volts (single-ended) *)
•
HTL signals at a 10 – 30 volts level
(alternatively differential with inverted signals A, /A, B, /B, or single-ended A, B only)
•
Impulses from photocells or proximity switches etc. providing a HTL level (10 – 30 volts)
•
Proximity switches according to NAMUR (2-wire) standard
(may need additional remote circuit)
*) requires special settings of the threshold parameters, see “Special parameters F10”
•
For applications based on different directions of rotation it is mandatory to
use quadrature encoders with channels A and B or with channels A, /A,
and B, /B (90° phase displacement).
•
Where the impulse level is HTL (10 – 30 volts) you can use either single-
ended signals (A and B only) or differential signals (A, /A, B, /B)
•
Where the impulse level is TTL, it is strictly recommended to use symmetric
differential signals (with inverted channels /A and /B).
Under industrial environment conditions, single-ended TTL signals may cause
serious problems due to insufficient EMC immunity of the signal lines