adept technology AdeptThree, User Manual, Page: 48 / 70

AdeptThree User's Guide
40
Solenoid Drivers
Two spare solenoid drivers are provided on the Tower PCA: Sig-2025
and Sig-2026. These are directly switchable from V or V
+
by utilizing
software signals 2025 and 2026, respectively. Refer to the SIGNAL
command in the V and V
+
Reference Guide for additional information.
The actual driver transistors are located on the Robot Signature Card
(RSC), at the base of the robot, and interface to the Tower PCA at J7
(USER SOL) via the robot harness. Refer to Table 3-1 for pin assignments
and Figure 3-11 for the connector's location.
Each driver is designed to handle 12 VDC solenoids at up to 500 mA,
similar to the hand OPEN/CLOSE solenoids. To overcome the
customary problem of dirt buildup at the solenoids, special circuitry has
been incorporated to provide a momentary 24 V initial pulse to the
solenoid to break any stiction, dropping to 12 V for holding.
Some solenoid manufacturers include a transient-suppression diode
across the leads of their solenoids. If such a diode is installed on the
solenoid you have selected, verify that the polarity is correct. A reverse
installation will short the diode across the driver circuitry. The User is
cautioned to use solenoids similar in design to the ones used for the hand
OPEN/CLOSE lines and to carefully check the wiring polarity before
applying power.
CAUTION
The solenoid driver hardware has no current limiting
capability and will attempt to drive a solenoid with as
much current as the impedance of the solenoid will accept.
As a result, if the User accidently shorts the so/-
leads together, the driver circuit will "over-current" and
fail. The RSC will then have to be repaired before that User
solenoid can be reused.