Troubleshooting — 15
Notes
Rev 3-97
* School
No: Often equipment located in remote locations may lose power without any
notification to the operator. Most IQ components have drop-out relays so that
if power is lost loop continuity will be maintained, but the components will still
remain off line.
Question 4I: Is fiber optic cabling being used?
Yes: The problem is likely to be a fiber termination or possibly a tranceiver. Try
running the loop on standard wire, or at least test the part(s) of the system that
are at distant locations by going to those locations and testing the loop a room
of components at a time. This will require taking the computer and interface to
the physical location(s) of the equipment on the loop. Note that just because
fiber optic cable is being used a Repeater may still be required.
No: Proceed to question 4J.
Question 4J: Is an IQ-INT II being used as system interface?
Yes: Check to make sure that a loop input and output are not connected across
two different interface loop connections.
No: Proceed to question 4O.
Question 5: Do all components remain on line with the computer?
Yes: From a communication standpoint the system is operating properly. If
problems occur with individual components that are not a function of system
design or programming contact Crown.
No: Proceed to quesion 5A
Question 5A: Does the computer have a 16550 UART for the com port?
Yes: Proceed to question 5B.
No: Install a com port board with the 16550 UART chip. This UART supports
higher speeds and includes additional memory buffers. It is commonly used
with high speed modems, however a standard RS232 com port is required for
IQ. If the problem continues proceed to question 5B.
Question 5B: Is loop capacitance under 30 nF?
Yes: Proceed to question 5C.
No: Remember to add 60 pF per component to capacitance calculations. In
cases where total capacitance is marginal loop operation may be intermittent.
Question 5C: Is a mixer being used as system interface?
Yes: Remember that mixers should not be used as the interface in large
systems. You cannot use a mixer as an interface for IQ2 components.
No: Proceed to question 5D.
Question 5D: DOS Software—Do you lose communication with the system
when you move the mouse or perform intense work with graphic objects?
Yes: There is probably a mouse driver conflict or internal computer hardware
problem. This may not be correctable without using a different computer. Try
a different mouse driver or try loading the mouse into a different memory area.
Crown recommends Logitech as the mouse of choice.
No: Proceed to question 5E.
Question 5E: Do you receive Break Detect warnings?
Yes: If you got past the first two questions without a problem there is likely to
be a loop capacitance problem or an intermittent connection somewhere in the
loop. Return to question 4 and proceed through the appropriate steps.
No: Contact Crown.
