Siemens 125-3208 operating instructions Contactors, Keypad Functions

SED2 VFD Electronic Bypass Option Operating Instructions

Contactors

The Controller board provides two or three relay contact circuits controlled by the Electronic Bypass Option: bypass, input, and output contactors. Each circuit includes a NO relay. Controller board connector J7 enables circuit connections. The relay circuits route power to the SED2 and the motor via the contactors. Controlling the contactors through the relay circuits is the main function of the Controller board.

Bypass Contactor – The bypass relay on the Controller board controls the bypass contactor. The output and bypass relays are interconnected to 120 Vac Hot. This enables a safety circuit that prevents the bypass and output contactors from simultaneously being energized.

Output Contactor – The output relay on the Controller board controls the output contactor.

Input Contactor – The input relay on the Controller board controls the optional input contactor.

Keypad Functions

VFD0096R1

			Bypass		VFD			Bypass
	Input		Hand		Input	Input		Hand
	Contactor		Start		On/Off	Contactor		Start
	Bypass					Bypass
	Contactor					Contactor
	VFD					VFD
Enable	Overload		Remote		Enable	Overload		Remote
			Start					Start
	Relay					Relay
	Output					Output
	Contactor					Contactor
	Motor					Motor
STOP	AutoBypassEnabled		VFDFault		STOP	AutoBypassEnabled		VFDFault
RESET			SafetyFault		RESET			SafetyFault
				VFD0097R1
	EssentialServices		OverloadFault			EssentialServices		OverloadFault
	Enable	Commanded Proofed				Enable	Commanded Proofed
INTERLOCKSTARTLOGIC					INTERLOCKSTARTLOGIC

2-CONTACTOR KEYPAD 3-CONTACTOR KEYPAD

Figure 4. E-Bypass Keypad Indicators and Pushbuttons.

The keypad provides user interface indicators and pushbuttons. The following table describes specific pushbutton and indicator functions:

6 Siemens Building Technologies, Inc.