Hardware Faults - Omron NT20S Operation Manual

Hardware Faults

7-1 Hardware Faults
NT20S Symptoms
POWER LED fails to
come ON
Nothing is displayed on
the screen (it is
completely white).
Communication with the
support tool not possible.
Cannot communicate with
the PC/Host.
Buzzer sounds, RUN LED
is OFF.
Touch panel does not
respond
PC mode changes to
monitor mode.
236
When a fault relating to the operation of the NT20S occurs, find the symptoms in
the table below and respond by following the corresponding "Remedy" indicated in
the table.
Cause
Power is not being supplied.
Power supply fuse has blown
Screen #0 has been read at the host
side.
The Transmit Mode has not been
established.
Not connected to the support tool.
The PT type/direct connection
settings made at the support tool do
not agree with the NT20S.
Memory switch settings do not
match.
NT20S and PC are not correctly
connected.
When NT link (1:N), there is unit
number duplication.
Power not supplied to the NT20S,
PC, or host
Malfunction due to external noise.
Malfunction due to external noise
Touch panel is broken.
The NT20S changes the mode
during host link communication.
Remedy
Check the connections and make sure that power is
supplied correctly.
(Refer to "2-2-3 Power Supply Connection", page 29.)
Contact your OMRON service center.
This is not an error. Change the screen number.
(Refer to "4-3 Screen Display", page 122.)
Display the system menu and select the Transmit
Mode.
(Refer to "3-6 Registering the Screen Data", page 86.)
Check the installation of the connector cable.
(Refer to "2-3 Connecting to the Support Tool", page
31.)
Make the PT type setting and direct connection setting
in the "tool settings" of the support tool agree with the
NT20S.
Check the communication setting in the "Memory
Switch" menu of the Maintenance Mode, and match
the PC and NT20S settings.
(Refer to "3-5 Setting the Conditions of
Communications with the PC/Host by Using the
Memory Switches", page 75.)
Check that the type, length and installation of the
connector cable match the specifications.
(Refer to "2-4 Connection to a PC by the Host Link",
page 32, "2-5 Connection to a PC by the NT Link",
page 45, and "2-8 Host Connections by RS-232C",
page 63.)
Set again with no duplication.
Check the power supply.
Distance the communication cable from the source of
the noise and insert a noise filter in the power supply
line.
Distance the communication cable from the source of
the noise and insert a noise filter in the power supply
line.
Check the touch panel by performing the touch panel
test in the I/O check in the maintenance mode.
This is normal with the NT20S specification. When
using a PC that can also be connected using the NT
link, connect it with the NT link (the mode is not
changed when using the NT link).
Section 7-1