41
the controller. To measure the 24 VAC, connect the meter to J1 terminal 1 and 2
on the power supply board. To measure the 12 VDC to the controller, connect
the meter set in volts DC to J4 terminal 1 & 2 on the power supply board.
3.3 Intellisys 24 VAC Supply:
Background
The Intellisys power supply is fed from the 24 VAC secondary of the control
power transformer T1. The expected reading of the 24 VAC signal should have a
tolerance of +/-15 %. The 24 VAC is fed to the power supply board through the
J1 connector. The signal is rectified by diodes. The resulting rectified DC signal
is approximately 12 VDC. The Intellisys is designed to accommodate +/- 25 %
tolerance. Deviations in excess of +/-25%, or a loss of this signal, can cause the
machine to shut down and reset to “Ready to Start”.
Procedure
This voltage measurement can be made with a Fluke 87 meter (or equivalent). A
recording meter (Fluke 87) is preferred for intermittent problems. Set meter for
volts AC and connect as noted.
Connect from J1-1 to J1-2.
Expected value = 24 VAC +/- 3.6 VAC
Set meter to volts DC
Connect from J2-1 to J2-2.
Expected value = 12 VDC +/- .6 VDC
If the expected values are not observed, possible causes may include:
Primary voltage in excess of 15% tolerance.
Wiring fault: Check primary and secondary wiring for errors, loose connection or
crimp, frayed ends, insulation breakdown, moisture contamination.
Fuse problem: Blown fuse (primary or secondary), loose connection, voltage
drop across fuse: >.5 VAC, excessive control system current: Remove power and
disconnect all but J2 connector to Intellisys (also remove option prom and
communications wiring). Apply power and record measurements. If
measurements return to normal, repeat procedure and use process of elimination
to find cause.
3.4 External 5 VDC Short Circuit:
Background
The Intellisys provides two 5 VDC signals for external use. The logic supply
voltage is used by the Intellisys to supply power for internal circuitry such as the
EPROM, RAM, Microprocessor, etc. The logic supply is also used to supply
power to an external device known as the “Option Module”. This connection is
To Next Page
Loading...
Need help?
General
