Siemens SAMMS-MV

4 Troubleshooting

Troubleshooting Guide

Error Condition Main Cause Remedy

Incomplete

Sequence Indicates the SAMMS-MV unit does not

detect current one second after a start

command, or it detects current one

second after a stop command.

If the unit trips one second after start, verify that

current transformer secondary input is present in the

range of 100 mVAC to 3.54 VAC at terminals 1, 2,

and 3 with reference to 4. Verify that the coil voltage

is 115 VAC at terminals 14, 15, or 16 with reference

to 13 when the motor is started. Verify 115 VAC at

terminal 7 with reference to 13. Correct conditions if

necessary. Call Siemens if unit continues to trip.

If the unit trips one second after a stop command,

verify the contactor is open. Repair or replace the

contactor if it is not functioning properly.

Verify operation of mechanical interlock, and replace

or adjust.

Verify absence of voltage at terminals 1, 2, and 3 with

reference to 4, and at terminals 14, 15, or 16 with

reference to 13. If voltage is present, define the

source and reconnect so that the motor current only

passes through the current transformer.

To disable incomplete sequence, select F1 on the

HHC, press the ENTER key for one or more seconds

and start the motor. The incomplete sequence will

remain disabled until the above procedure is

repeated.

External Trip If the external trip LED is solidly

illuminated and the motor is stopped, it

indicates a jam or loss of load

condition, or a trip caused by an

overtemperature indication from an

RTD.

Jam conditions such as a blocked conveyor belt or

gear train cause a sudden increase in motor current,

which can damage the motor’s insulation in a short

period of time.

Loss of load conditions, such as a broken blade of an

impeller or loss of back pressure of a pump, result in

a sudden decrease in motor current.

RTD trip indicates that the stator temperature or the

temperature of one of the bearings has exceeded its

threshold.

RTD stator trip indicates either that the motor cooling

system is blocked, or that the fan is broken.

RTD bearing trip indicates overheating of the motor or

load bearings.

In any case, the motor should not be restarted until

the cause of the overheating has been corrected.

F16 on the HHC displays the external trip current at

the time of the trip, or the RTD number which caused

the trip.

In any case, determine the reason for the external trip

and correct the problem before restarting the motor.

If the external trip LED flashes and the motor

continues to run, it indicates loss of load warning or

process current warning.