Emerson P/N 400518-02 manual Differential Source, Single Ended Source

Epsilon EP-I Indexing Drive and FM-2 Indexing Module Reference Manual

Differential Source

The Differential setting (default) is perfect for most encoders or upstream drives. The differential input circuit is RS-422 compatible making it inherently noise immune while being able to accept pulse rates of up to 1.75 Mhz per channel.

Single Ended Source

The Single Ended setting is a good match for any open collector driver that requires an external pull up resistor making it ideal for most stepper controllers, PLC stepper cards and PC computer parallel printer ports. The single ended inputs use high noise immunity circuitry and have internal pull-up resistors to the drive’s 5 Volt logic supply so external pull-ups and biasing circuitry is not required.

The two hardware input circuits are included in the drive and are accessible through the drive command connector. When proper installation techniques are followed as shown below, the differential input setup will provide a more robust and noise immune system than a single ended input setup.

Differential input is recommended under any of the following conditions:

•Pulse width < 2 µs

•Pulse frequency > 250 kHz

•Pulse command cable length > 25 feet

•Noisy electrical environments

Differential input circuit specifications:

Input frequency maximum:	1.75 Mhz
Input device:	AM26C32
Input impedance:	12 Kohms each input

Maximum voltage applied to input pins (A, A/) or (B, B/):

Single Ended (referenced to 0V drive logic):+/-10 V

		Differential (referenced to mating differential input):+/-10 V
Maximum common mode voltage:			+/-7 V
Minimum differential voltage required: 200 mV
Input voltage hysteresis:			60 mV
Epsilon EP-I Wiring Example:
	STI-SNCI Terminal	Sync Connector Pin #	Pulse-Direction	Pulse-Pulse	Pulse Quadrature
			Signal	Signal	Signal
	Sync Enc In “A”	1	Pulse	Pulse +	A
	Sync Enc In “A/”	2	Pulse/	Pulse +/	A/
	Sync Enc In “B”	3	Direction	Pulse -	B
	Sync Enc In “B/”	5	Direction/	Pulse -/	B/

Single ended input circuit specifications:

Single ended input specifications:

1 MHz input frequency maximum

Internal 330 ohm pull-up resistors to 5 Volt (non-isolated)

1.5V low level

3.5V high level

Output driver requirements:

15 mA sinking (open collector)

5 V capacity

74