Controller Used in Automatic Transfer Switch

Model	Function	Matchable model
YCU-A	Detection of over-voltage, under-voltage and the lack of phase fault of two lines power supply	YCU-××N. YCU-××T. YCU-××M. YCU-××Q
YCU-B	Detection of over-voltage, under-voltage and the lack of phase fault of two lines power supply; control generators and incorrect operation	YCU-××N. YCU-××T. YCU-××M. YCU-××Q
YCU-C	Detection of over-voltage, under-voltage and the lack of phase fault of two lines power supply; control generators and incorrect operation	YCU-××TN(Out of supplying)
YCU-D	Detection of over-voltage, under-voltage and the lack of phase fault of two lines power supply; control generators and incorrect operation	YCU-××C Namely(YCU-××N. YCU-××with wire connection )

Connection Terminals Diagram of YCU-A-type Controller:
-A1, B1, C1, N1 connect three-phase four wire system of main power supply, if connected three-phase three wire,N1 grounding.
-A2,B2,C2,N2 connect three-phase four wire system of stand-by power supply, if connected three-phase three wire,N2 grounding.
- L1 connects the main power phase A through the auxiliary contact in the switch; it is the main power brake indicator.
- L2 connects the stand-by power phase A through the auxiliary contact in the switch; it is the stand-by power closing indicator.
-M1, M2, M3, M4 are out-put terminals of switch.

Brief Functional Introduction of YCU-B-type Controller
Compatible with all the function of YCU-A-type controller;
Adding over voltage detection of two-path power;
Providing generators start signal (delayed about 3 S to issue when a main power fails), When you order, please indicate electricity grid – Generators.

Main Characteristics of YCU-A-type Controller:
Adopt single chip to stop program control ;
Logical program and electric dual linkage;
Compact design make it available to be placed in switch cabinet panel for observation, operation and running;
A strong anti-electromagnetic interference performance.


Connection Terminals Diagram of YCU-B-type Controller:
-A1, B1, C1, N1 connect three-phase four wire system of main power supply , if connected three-phase three wire,N2 grounding
-A2,B2,C2,N2 connect three-phase four wire system of stand-by power supply, if connected three-phase three wire,N2 grounding
-When L1 connects the main power phase A through the auxiliary contact in the switch, the main power will close.
-When L2 connects the stand-by power phase A through the auxiliary contact in the switch, the stand-by circuit will close.
-M1, M2, M3, M4 are switching out-put terminals.
-F, F1, F2 are generator start signal output terminals, F is the public terminal, when the main power is normal, F will closes with F2, F and F1 disconnect ;when the main power become abnormal and the stand-by power has no power , F and F1 will close after three seconds , while F and F2 will disconnect.

Brief Functional Introduction of YCU-C-type Controller:
YCU-C-type controller used to control the three segments TN type ATS that composed of three coins.
A dedicated cable used to connect the switch and the controller and makes it easy to install;
Detect the two-path power over-voltage, under-voltage, lack phase, ect;
Make the TN-type ATS disconnect the two-way power at the same time, convenient to overhaul;
Provide generators start signal (delayed about 3 S to issue when the main power fails).


Connection Terminals Diagram of YCU-C-type Controller:
-F1, F, F2 are used to start generator, F is the public terminal, when the main power is normally closed, F2 is normal-shut terminal; when the main power became abnormal, it will delay about 3 S to close;
-When R1, R2 are connected, the controller will be in unallowable state: (R1, R2 can only connect passive contact, or it will damage the controller);
-L1, L2 can be added more functions according to the request of users (standby).
Unallowable State of YCU-C-type Controller:
When R1, R2are connected, the controller will be in an unallowable state, and then the lights will flash at the same time.
1. When connecting terminals R1, R2 means to press a manual reset button and then it will be in unallowable states, at this time, controllers will not respond no matter how to press main power transform button, backup power transform button or even returning to the automatic mode.
2. In automatic mode, connecting terminals there is no place for R1, R2, to reset, and just be in unallowable state but not respond to external conditions.
3. Cutting off the two-path power, and connecting terminals R1, R2 makes the controller in unallowable state to avoid dangers to maintainers by misusing.


Brief Functional Introduction of YCU-D-type Controller:
YCU-D-type controller used to control the two segments TN type ATS composed of two coins.
A dedicated cable used to connect the switch and the controller and makes it easy to install;
Detect the two-path power over-voltage, under-voltage, lack phase, etc.
Provide generators start signal (delayed about 3 S to issue when the main power fails).

Connection Terminals Diagram of YCU-D-type Controller:
-F1, F, F2are used to start generator, F is the public terminal, when the main power is normally closed, F2 is normal-shut terminal; when the main power became abnormal, it will delay about 3 S to close;
-When R1, R2 connect, the controller will be in unallowable state: (R1, R2 can only connect passive contact, or it will damage the controller)
-L1, L2 can be added more functions according to the request of users (standby).
Controller Used in Automatic Transfer Switches