Specifications

ST900 Family General Handbook
667/HB/32900/000 Issue 12 Page 68 of 265
lengths using the table, each tactile unit should be considered to be a 12W
load.
If required to reduce core usage, tactile units may share a return core with
any Red/Amber LED signal return core on the same pole (NOT green as this
must always have its own return). If this option is exercised each tactile
should be considered to be a 45W load for the purposes of assessing
acceptable cable run lengths using the table. This figure is much higher than
their normal running power, but is typical of the power consumed if the tactile
device is physically held, stopping the motor.
7. The ELV solar cell should be provided with a drive and return core for
connection of the solar cell supply and signal. The solar cell return can be
commoned with the LED signal return. Its effect on the voltage drop is so
small that it can be ignored.
8. Returns for digital inputs (for above ground detectors and pushbuttons etc on
the same pole) may be commoned together, but must remain separate from
the LED signal returns.
9. Audible units must be provided with a separate drive and return core.
Audible units on the same Audible Driver Module may share a common drive
and return core (up to 250m) if required to reduce core usage, but must
remain separate from the LED signal returns and digital input returns.