Issue:
How to lockout a circuit?
Resolution:
Circuit Lockout (RTAA, RTWA, RTUA) :
RTAA 130-400 TON: Circuit lockout can be accessed in the P1 menu, item 1A. Select each circuit and set to either enable or disable. Circuit lockout is different than external circuit lockout. Frequent errors are made when technicians enable external circuit lockout rather than (local) circuit lockout in the P1 menu.
RTAA 70-125 TON: Circuit lockout can be accessed in the Service Tests sub menu. Press next until reaching the display screen Circuit Lockout Ckt1/Ckt2 enable/disable and set appropriately. Frequent errors are made when technicians enable external circuit lockout (Service Settings sub menu) rather than (local) circuit lockout in the Service Tests sub menu.
RTWA 70-125 TON: Circuit lockout can be accessed in the Service Tests sub menu. Press next until reaching the display screen Circuit Lockout Ckt1/Ckt2 enable/disable and set appropriately. Frequent errors are made when technicians enable external circuit lockout (Service Settings sub menu) rather than (local) circuit lockout in the Service Tests sub menu.
RTUA 70-125 TON: Circuit lockout can be accessed in the Service Tests sub menu. Press next until reaching the display screen Circuit Lockout Ckt1/Ckt2 enable/disable and set appropriately. Frequent errors are made when technicians enable external circuit lockout (Service Settings sub menu) rather than (local) circuit lockout in the Service Tests sub menu.
External Circuit Lockout:
The UCM provides auxiliary control of a customer specified or installed contact closure, for individual operation of circuits. If the contact is closed, the refrigerant circuit will not operate. The refrigerant circuit will operate normally when the contact is opened.
RTAA 130-200: To install, cut, strip and wire-nut existing wire loop #W59 on the P43 connector of the 1U4 (#W60 on the P53 connector of the 1U5) module to low voltage leads 45A and 45B (46A and 46B). Connections are shown in the field diagrams which are shipped with the chiller.
- External circuit lockout will only function if menu item 3b is enabled.
- A contact closure will not allow the circuit to run. An open contact will allow the circuit to run normally. (Note that the wording on page 71 of RTAA-IOM-3 is incorrect for this logic)
RTAA 240-400: To install, cut, strip and wire-nut existing wire loop #W53 on the P43 connector of the 1U4 (#W55 on the P53 connector of the 1U6) module to low voltage leads 568 and 569 (566 and 567). Connections are shown in the field diagrams which are shipped with the chiller.
- External circuit lockout will only function if menu item 3b is enabled.
- A contact closure will not allow the circuit to run. An open contact will allow the circuit to run normally. (Note that the wording on page 71 of RTAA-IOM-3 is incorrect for this logic)
RTAA 70-125: To install, cut, strip and wire-nut existing wire loop#W7 on the P43 connector of the 1U4 (#W4 on the P53 connector of the 1U5) module to low voltage leads 45A and 45B (46A and 46B). Connections are shown in the field diagrams which are shipped with the unit.
- External circuit lockout will only function if External Circuit Lockout (Service Setting Menu) is enabled.
- A contact closure will not allow the circuit to run. An open contact will allow the circuit to run normally.
RTUA 70-125: To install, cut, strip and wire-nut existing wire loop#W7 on the P43 connector of the 1U4 (#W4 on the P53 connector of the 1U5) module to low voltage leads 45A and 45B (46A and 46B). Connections are shown in the field diagrams which are shipped with the unit.
- External circuit lockout will only function if External Circuit Lockout (Service Setting Menu) is enabled.
- A contact closure will not allow the circuit to run. An open contact will allow the circuit to run normally.
RTWA 70-125: To install, cut, strip and wire-nut existing wire loop#W7 on the P43 connector of the 1U4 (#W4 on the P53 connector of the 1U5) module to low voltage leads 45A and 45B (46A and 46B). Connections are shown in the field diagrams which are shipped with the unit.
- External circuit lockout will only function if External Circuit Lockout (Service Setting Menu) is enabled.
- A contact closure will not allow the circuit to run. An open contact will allow the circuit to run normally.
Notes:
See appropriate IOMs for additional assistance.
Changes:
Other Question/Problem/Cause Statements:
- How to lockout a circuit?
- Circuit Lockout or External Circuit Lockout?
- External Circuit Lockout?
- Chiller will not start; circuit A locked out...now circuit B will not start?
- Chiller will not start; circuit B locked out...now circuit A will not start?
- How can I run one circuit at a time to check out the compressors?
- How could I disable one of the two circuits for load shedding?
- Customer would like to disable remotely?
Facts:
- Air-Cooled Chiller (Pueblo) (RTAA 70-125 Ton)
- Compressor Chiller (Pueblo) (RTUA)
- Water-Cooled Chiller (Pueblo) (RTWA)
- Air-Cooled Chiller (Charmes) (RTAA)
- Air-Cooled Chiller (Pueblo) (RTAA 130-400 Ton)
Document Identifier: DOC-82204
Document Identifier: 82204
WARNING:
Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.