Carrier HS070-160 Troubleshooting Manual page 25

EXV Driver Module (Fig. 16.)
When 24 vat are applied across
channel it is read as an ON signal. Zero voIts is read as
an OFF signal.
drive the electronic expansion valves, Terminals I and 7
supply voltage to the valves. Terminals 2 through 5 and 8
through 1 I connect the individual coils (4 per valve) to
neutral in a repeating sequence to drive the valves in
incremental steps.
S E N S O R B U S C O N N E C T O R
RED STATUS LIGHT ~
C O M M U N I C A T I O N
STEPPER
MOTOR 2
J4 -
STEPPER
MOTOR I
Fig. 16 - EXV Driver Module (DSIO)
G R O U N D ( C )
COIL 4
COIL 4
3
2
I
C O M M O N
A D J U S T M E N T
ON UNDERSIDE
function of the HSIO is to allow the operator I(.) cr)&*
set schedules.-
Fig. 17 - Keyboard/Display Module (I-ISIO)
2 5