Issue:
What can limit the maximum FLA of the TeSys T overload relay?
Product Line:
TeSys T Motor Management Controller
Environment:
Products Sold in North America
Cause:
Installation and Programming
Resolution:
There are three sizes of TeSys T overload relay, the LTMR08, LTMR27, and LTMR100.
The devices have the ranges below without external CTs and with no modifications made in the programming:
This means that with no modification of settings or addition of external CTs these devices will have a maximum FLA of 8, 27, and 100 amps respectively.
If you add external CTs, and program this via SoMove or the HMI, the maximum and minimum FLA value can increase. If you have your wire pass through the internal CT window of the device multiple times, and program this via SoMove or the HMI, your FLA min and max values will decrease.
But those aren't the only parameters that will affect the FLA range of your TeSys T. The "Contactor Rating" will also affect the range, and if the contactor rating is lower than the default maximum of the device, or even lower than the range would be with CTs, this will be your new maximum FLA.
For example if you have an LTMR08 with 300:5 external CTs and one pass through the internal CT window your LTMR FLA range should be 24-480 amps. If you have this device on the output of a NEMA size 4 starter though your contactor rating should be programmed to 135 amps, due to this your overload range will still have a minimum of 24 amps but the maximum value will now be 135 amps.
What can limit the maximum FLA of the TeSys T overload relay?
Product Line:
TeSys T Motor Management Controller
Environment:
Products Sold in North America
Cause:
Installation and Programming
Resolution:
There are three sizes of TeSys T overload relay, the LTMR08, LTMR27, and LTMR100.
The devices have the ranges below without external CTs and with no modifications made in the programming:
| LTMR08 | .4-8 amps |
| LTMR27 | 1.35-27 amps |
| LTMR100 | 5-100 amps |
This means that with no modification of settings or addition of external CTs these devices will have a maximum FLA of 8, 27, and 100 amps respectively.
If you add external CTs, and program this via SoMove or the HMI, the maximum and minimum FLA value can increase. If you have your wire pass through the internal CT window of the device multiple times, and program this via SoMove or the HMI, your FLA min and max values will decrease.
But those aren't the only parameters that will affect the FLA range of your TeSys T. The "Contactor Rating" will also affect the range, and if the contactor rating is lower than the default maximum of the device, or even lower than the range would be with CTs, this will be your new maximum FLA.
For example if you have an LTMR08 with 300:5 external CTs and one pass through the internal CT window your LTMR FLA range should be 24-480 amps. If you have this device on the output of a NEMA size 4 starter though your contactor rating should be programmed to 135 amps, due to this your overload range will still have a minimum of 24 amps but the maximum value will now be 135 amps.
Released for:Schneider Electric USA
