TOSHIBA- 67
TX Series 48 - 1250A
Chapter 7 - Maintenance and Troubleshooting
The TX Series is designed to be a maintenance-free product. However, as with all electronic equipment, the unit
should be checked periodically for dirt, moisture or industrial contaminants. These can cause high voltage arc-over,
carbon tracking or prevent proper cooling of the SCR heat sinks. All bolts should be checked annually for proper
tightness using an accurate torque wrench .
Note: If the unit is installed in a contaminated environment and forced air cooling is used, blower filters must be
checked and cleaned regularly to insure proper air flow and cooling of the enclosure.
7.1 - Failure Analysis
When a fault occurs, the LCD will display the fault error and the listed LED and AUX Relay will be lit. Please clear all
faults before attempting to restart the unit. Note: If the problem persists after the required programming changes have
been made, and all corrective action has been taken, please contact the factory for assistance.
Problem CPU LCD Display LED
Aux
Relay
Possible Cause Solutions
Short circuit or ground fault
in motor/cabling
Locate and remove short or ground
Phase Loss Repair cause of phase loss
Branch circuit protection
not correctly sized
Verify correct sizing of branch circuit
protection
Faulty main circuit board
Remove power and replace main circuit
board.
Faulty SCRs
Remove power and test SCR(s). Refer to
Section 7.1.1 for the SCR testing
procedure
Single phase incoming
power
Correct problem with incoming power
Faulty SCRs
Remove power and test SCR(s). Refer to
Section 7.1.1 for the SCR testing
procedure
Fan(s) not functioning
(If supplied)
If fans have power, remove power and
replace fan(s). If fans do not have power
find cause of power loss and repair.
Heatsink coated with dirt
Remove power and clean heatsink with
high pressure air (80 - 100 psi max clean
and dry air)
Overcurrent on unit
Verify that running current does not
exceed unit rating
Environment temperature
over 122° F (ambient
temperature for chassis
units) or over 104°F
(ambient temperature for
enclosed version
Place unit in environment temperature
less than 122°F for panel version or less
than 104°F for enclosed version.
Bypass failed to close Check bypass contactor and wiring
Loss of 1or more phases of
power from utility or
generated power
Check power source
Blown power fuses Check for short circuits
Phase Loss
PHASE LOSS
Trip AUX1
Trip
Trip
AUX1
AUX1
Thermostat trips
during run
EXTERNAL TRIP ON
THERMOSTAT
Trip AUX1
Short Circuit Trip
SHORT CIRCUIT TRIP
Single Phase Trip
SINGLE PHASE TRIP
(Check LCD display for
possible fault indicators)
