STP-301/451 Series Instruction Manual 
 
6-3
Installation 
6.1.2 Rear Panel 
 
◇ 
A hazardous live voltage may exist at connector/terminal that marked 
 
. 
DO NOT touch the terminal. Doing so may result in electric shock. When operating 
connection/disconnection to connector, always power OFF the STP pump (Switch 
the breaker "OFF"). 
 
(13) AC POWER Connector (CON1) 
A maximum voltage: Equal to the input voltage of this connector. (MAX 240VAC) 
z  For primary power input. 
 
(14) MAIN POWER Breaker 
z  Switches ON/OFF the primary power. 
z  A metal fitting is attached to secure the breaker at the OFF position. 
 
(15) P. CONNECTOR (CON2) 
A maximum voltage: 62VAC 
z  For connection of the STP connection cable. 
 
(16) Ground Terminal 
z  For connection of the ground cable between the STP pump and the STP control unit. 
 
(17) I/O TB1 Terminal Block 
A maximum voltage: Equal to the input voltage of this connector. (MAX 240VAC) 
z  For remote output signals. 
 
(18) I/O TB2 Terminal Block   
A maximum voltage: Equal to the input voltage of this connector. (MAX 240VAC) 
z  For remote input signals. 
 
(19) F1 Fuse(250 V,10 A) 
(20) F2 Fuse(250 V,10 A) 
z  For protection of optional power supply for the I/O TB1 terminal block. 
 
(21) CON 4 Connector (Optional accessory) 
A maximum voltage: Equal to the input voltage of this connector. (MAX 125VAC) 
z  For remote input/output signals. 
This connector can maintain compatibility with the remote I/O signal of the 
STP-200/300/400 series.