TANDBERG 7000MXP User Manual page 217

Peripheral Equipment
RS366:
All balanced inputs and outputs (A and B) use balanced line signals according to V.11 (RS422)
and single ended signals in accordance with V.10 (RS423).
For balanced signals a "0"=low voltage is defined as terminal A positive with respect to terminal
B.
For unbalanced signals a "0"= low voltage is defined as terminal positive with respect to GND.
Cable length max: Leased Line Control = 20 Meter
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