KEP SC-FF Operating Manual

SC-FF Series

Frequency Scaler & Pulse Isolator

http://www.kep.com

99616 10/9/98

KESSLER-ELLIS PRODUCTS

10 Industrial Way East
Eatontown, NJ 07724
800-631-2165 • 732-935-1320
Fax [phone]

INDEX

DESCRIPTION ..................................................................................1

SPECIFICATIONS.............................................................................1

WIRING HOOKUP.............................................................................1

INPUT & OUTPUT SETTINGS..........................................................2

REMOVING THE CASE .........................................................2

PULSE SCALING ...................................................................2

PULSE DURATION ................................................................2

OUTPUT ADJUSTMENTS .....................................................2

RESPONSE TIME SETTINGS ...............................................2

LED INDICATORS..................................................................2

DIMENSIONS....................................................................................3

WARRANTY ......................................................................................3

DECODING PART NUMBER ............................................................3

SC-FF Signal Conditioner

DESCRIPTION:

The SC-FF is a DIN rail mount, DC powered frequency scaler and
pulse isolator. On the isolated pulse output, the SC-FF provides
an isolation barrier of 500V from the input signal. All SC-FF units
have an open collector pulse output with a maximum output
frequency of 10KHz. The standard unit also has an isolated pulse
output with a maximum count speed 1000 cps or 1KHz. The SC­FF also has an optional configuration with an output relay
replacing the isolated output. The relay output has a maximum
count speed of 10 cps or 10Hz.
The SC-FF supports several pulse input types. These input types
include magnetic pickup, contact closure, and an isolated pulse
input.
The pulse scaling permits a user to apply a scaling multiplier with
a value of 0.0001 through 0.9999 and dividers of 1, 10, 100, 1000,
and 10000. Pulse scaling is accomplished by rotary encoded and
dip switch selections.
The pulse output has user selectable output pulse duration and
internal pullup resistors. The user may select his pulse output
configuration by means of a dip switch.
The unit is powered by 8-35 VDC. Reverse polarity protection is
provided. Power and Pulse input/output indicators are provided.
The unit is available in enclosures intended for either DIN rail,
NEMA4X, or Explosion Proof

APPLICATION:

Frequency pulse scalers are often used to obtain pulse outputs in
engineering units. They are also used as pulse streching devices.
Many PLC inputs and electromechanical counters need long pulse
output durations. The SC-FF can be used as a pulse stretcher for
applications requiring long pulse durations.

OPERATION:

The SC-FF can accept a variety of input types such as Magnetic
pickup, Contact closure or Optically isolated pulse inputs. Output
scaling is accomplished via switch settings. These switch settings
allow the unit to divide or multiply the input frequency to obtain the
desired scaling factor.

Simplified Block Diagram

mV

Input

3-30V

Input

Contact
Closure

DC

Input

1

2

5

6

3

4

7

8

+
–

10kΩ

10kΩ

3.3kΩ

+
–

Divider

LPF

+
–

+5V

5 V

Regulator

Select

Switch

Thumbwheel

.0000 to .9999

Pulse Duration

Monostable

500 µsec

Duration Select

Switch

Pulse Rate
Multiplier

Pulse Rate

Divider

1, 10, 100,

1000,10000

50 µsec

50 msec

Specifications:
Pulse Input:

Isolated Pulse:

Logic 1 (high): 3 - 30 VDC
Logic 0 (low): 0-0.4 VDC
0-10 kHz, 1 kΩ Input Impedance
Reverse Polarity Protection
Isolation Voltage: 500 V

Contact Closure:

Switch Debounce: 40 Hz maximum count rate
10 kΩ internal pullup to 5 VDC

Magnetic Pickup:

Sensitivity: 30 mV p-p
Bandwidth: 0-3500 Hz
Over Voltage Protection to 30 VDC
10 kΩ input resistance

Outputs:

Pulse Duration: 50 mSec, 50 µSec, 500 µSec (Switch selectable)
Pulse Output:

Maximum Voltage: 48 VDC
Maximum Sink Current: 100 mA @ 1.0V max

Max. Output Speed: 10 kHz

Reverse Polarity Protection
Overcurrent Protection
Jumper selectable for 5V, 24V or open collector pulse output

Isolated Pulse Output (requires external pull-up resistor):

Maximum Voltage: 30 VDC
Maximum Current: 10 mA
Max. Output Speed: 1 kHz
Isolation Voltage: 500 VDC
Reverse Polarity Protected

Relay Output (optional):

Contact Rating: 0.5 amps 240 VAC
Output Form: Form A (SPST)
Max. Output Speed: 10 Hz

Power Input:

Input Voltage Range: 8.5 to 35 VDC
Supply Current: 25 mA (nominal)
Reverse Polarity Protection
Transient Protection

Pulse Scaling:

Scaler: 0.0001 to .9999
Divider: /1, /10, /100, /1000, /10000

Mounting Styles

DIN Rail Mount: Plastic enclosure with a snap fastener for

fitting to DIN 46 277 and DIN EN 50 022
assembly rails.

NEMA 4X: 4.92" x 4.92" NEMA 4X Enclosure for wall

mounting.

Explosion Proof: Aluminum enclosure for:

Class I, Division 1, Groups B, C & D
Class II, Division I, Groups E, F & G.

9

Pulse

Output

10

Isolated Pulse

Output

Relay

Output

(optional)

+
–

+

11

–

12

11

12

Pulse Output

LED Indicator

Wiring:

Common
Opto-isolator In (+)
Opto-isolator In (-)

Common

Isolated Pulse Out (+) / Relay Output

Isolated Pulse Out(-) / Relay Output

4 5 6

10 11 12

1 2 3

Magnetic pickup
Magnetic pickup
Contact Closure Input

7 8 9

(+) DC Power Input
DC Power Input Common

Pulse Output (+)

1

SC-FF Signal Conditioner

INPUT & OUTPUT SETTINGS

REMOVING THE CASE:

The case must be removed to change switch settings. To remove
the case procede as follows:

Refer to FIGURE 1. Using finger tips, carefully pry the case
away from the terminal blocks (as shown with dotted lines).

Pry far enough to release the restraining clips on both sides of
the case.

Press up on terminal block with thumbs. The assembly will
pop out allowing it to be removed from case.

FIGURE 1:

4 5 6

1 2 3

Pulse
Input

Power

OUTPUT ADJUSTMENTS:

Frequency Out =

Frequency In • Scaling Factor

Pulse Divider

PULSE SCALING FACTOR SWITCHES

Example:

5

6

4

3

2

9

1

0

0.1234 =

5

6

4

7

3

8

2

9

1

0

FIGURE 2:

5

6

4

7

8

7

3

8

2

9

1

0

5

6

4

7

3

8

2

9

1

0

7 8 9

10 11 12

PULSE SCALING:
Pulse scaling, pulse duration, and internal pullups are all
configurable with dip switches. Refer to the following tables to
configure the unit for your application.

FREQUENCY DIVIDING FACTOR:
The appropriate range is selected by turning “ON” the correspond­ing switch.

S1 S2 S3 S4 OUTPUT
on off off off /10000
on off off on /1000
on off on off /100
on off on on /10
off on X X /1

PULSE DURATION (for pulse & isolated pulse output):

S5 S6 Duration Max CPS

OFF OFF 50uS 10000

ON OFF 500uS 1000
ON ON 50mS 10

INTERNAL PULLUP RESISTOR VOLTAGE (for pulse output)

S7 S8 Pulse Output Voltage

ON OFF 5 VDC
OFF ON 24 VDC
OFF OFF Open Collector

1 2 3 4 5 6 7 8

ON

SW1 SW2 SW3 SW4

DIP Switch for Selecting

5

5

5

5

6

6

4

7

3

8

2

9

1

0

Pulse Scaling Switches

4

4

7

3

3

8

2

2

9

1

1

0

6

6

4

7

7

3

Frequency Divider,

8

8

2

9

9

1

Pulse Duration &

0

0

Pull-Up Resistors

LED INDICATORS:

The SC-FF has two LED's which indicate the status of the
unit. The table below describes the variouse states for the
LED's.

POWER LED: MEANING:
OFF The unit is off.

ON (constant) The unit is loop powered.
PULSE LED: MEANING:

BLINKING The unit is receiving an input fre-

quency. The LED will blink at a rate
proportional to the input frequency.

ON The unit is not receiving a pulse input.

(The LED may appear to be constantly
"ON" at high input frequencies)

2

Dimensions

SC-FF Signal Conditioner

DIN Rail Mount

WARRANTY

This product is warranted against defects in
materials and workmanship for a period of two
(2) years from the date of shipment to Buyer.

.89

(22.5)

Mounting holes molded
directly under cover screws.
Max. screw head .29"
(Typ. 4 places)

4.21

(107)

PANEL INSTALLED

5.06

(129)

1.40 (35.5)

2.95 (75)

NEMA4X

To access terminals, remove

4.21

(107)

4.92

(125)

TOP VIEW

cover and 4 panel screws.

4.92

(125)

.43

(11)

Explosion Proof Enclosure

3/4” NPT (2) HLS.
(feed thru hubs)

.18 (5)

SIDE VIEW

3.88 (98.5)

2.95
(75)

1.93
(49)

The Warranty is limited to repair or replace­ment of the defective unit at the option of the
manufacturer. This warranty is void if the prod­uct has been altered, misused, dismantled, or
otherwise abused.

ALL OTHER WARRANTIES, EXPRESSED
OR IMPLIED, ARE EXCLUDED, INCLUDING
BUT NOT LIMITED TO THE IMPLIED WAR­RANTIES OF MERCHANTABILITY AND FIT­NESS FOR A PARTICULAR PURPOSE.

Kessler - Ellis Products Co.

10 Industrial Way East

Eatontown, NJ 07724

(732) 935 - 1320

Toll Free 800 - 631 - 2165

Fax (732) - 935 - 9344

Decoding Part Number:
Example SC-FF 1 B ET
Series

FF= Frequency to Frequency

7.125
(181)

5.44

(138)

4.06

(103.2)

2 MTG LUGS

0.31 DIA.

Output T ype

1 = Open Collector & Isolated Pulse (STD)
2 = Open Collector & Relay Output

Mounting:

B= Nema 4X
C= Explosion Proof
D= DIN Rail

Options:

ET= Extended Temp: -4° to 185°F (-20° to 85° C)

Accessories: (add to end of part number)

DR-4= 4" DIN Rail

3