meM-INC
© BMC Messsysteme GmbH
Page 2
1 Start-up
procedure
Plug the red frames onto the short sides of the device with the feet looking downwards, as can be seen in the product
picture. Connect one end of the USB-cable to the device and the other to the USB-interface of the PC. The device is
supplied with power via the USB-connection.
2 Connection of incremental encoders
The
meM-INC
provides for 3 electrically isolated incremental encoder
channels (
low
: 0V..1V;
high
: 5V..30V). These can be reached at the 37-
pole Sub-D socket at the back of the device. For each incremental en-
coder there are lines for signal A, signal B and optionally the external
counter reset.
For further information about connecting your incremental encoder,
please refer to the relevant documentation of your product.
Pin (Sub-D37)
Inkremental Encoder No. / Connection
9(+), 28(-)
10(+), 29(-)
11(+), 30(-)
1 / signal A, counter input
1 / signal B, counting direction
1 / reset function
12(+), 31(-)
13(+), 32(-)
14(+), 33(-)
2 / signal A, counter input
2 / signal B, counting direction
2 / reset function
15(+), 34(-)
16(+), 35(-)
17(+), 36(-)
3 / signal A, counter input
3 / signal B, counting direction
3 / reset function
•
A high level of 30V may damage the meM-INC. To ensure that each pulse is registered please do not exceed
the maximum pulse frequency of up to 32kHz.
•
The optocoupler inputs are low-ohmic, for high input voltages the input current optionally may be limited
by a serial resistor (12V: max. R=820
Ω
; 24V: max. R=2,2k
Ω
).
3 Integrated
functions
3.1 Number of counting pulses
meM-INC
counts the number of incoming pulses measured at the connection of signal A. If the maximum counting
range is reached the counter is reset to 0. If the external counter reset is connected, the counter can be reset at any time.
Avoid any toggling of the encoder outputs while the incremental encoders stand still, as it leads to measuring errors!
3.2 Counting direction
The counter of the
meM-INC
can count up or down. This depends on the status of the connection for signal B (pin 10,
13, 16). If it is
low
, the counting pulses arriving at signal A are counted upwards. If signal B is
high
, the device counts
downwards. Not connected inputs are constantly
low
so that in this case the counter goes upwards.
3.3 Frequency measurement
In frequency measurement 3 gates - a time interval in which the number of counting pulses is measured - are provided:
0.1sec, 1sec, 10sec. Please note, that the higher the gates, the more exact the received frequency value will be, but on
the other hand calculation will take more time, as the values are provided not before the end of the gate.
