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Installation and Operating Instructions

Vari-Watt Power Controller

PK5550037-75459

October 2018

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The Chromalox Vari-Watt Controller accepts an analog control signal input and produces a proportional output signal to drive Solid State Relays such as the Chromal-ox SSR series. Demand Oriented Transfer (DOT) firing for each SSR provides precise control with resolution to 3 cycles (select 50 or 60 Hz operation).

In a typical application the Vari-watt is used to convert temperature/process control signal (4-20 mA) to a Zero Crossing SSR power control.

When using multiple SSR’s the Load Management fea-ture automatically offsets the turn-on signal for each SSR output to limit inrush current.

Manual control provides open loop control of the out-put from 0 to 100% with input from a 10K Potentiom-eter.

Auto/Manual Control allows a single pole switch to select between Manual Control or Automatic Control from any of the analog signal inputs.

• Allows Automatic or Manual Control of Heater Loads Using Chromalox SSR Series Solid State Relays

• Demand Oriented Transfer (DOT) Firing for Analog Inputs

• 50 or 60 Hz (Jumper Selectable)

• Load Management Feature for Multiple SSR’s

• Analog Inputs

• 4-20 mAdc

• 0-5 Vdc

• 0-10 Vdc

• 50 or 60 Hz Operation, (Jumper Selectable)

• Open Board Design

• DIN Rail Mounting

Instrument power: • 95 to 250 Vac power, less than 15VA

Operating Environment: • 32-150°F ambient temperature • Relative humidity less than 95% non-condensing.

Analog Input types: • 4-20 mAdc into 250 Ohm • 0-5 Vdc into 10K Ohm • 0-10 Vdc into 20K Ohm • 10K potentiometer

Outputs (Up to 4 total): • SSR drive (12 Vdc at 100 mAdc (total current for

outputs))

DOT timing: • 3 cycle, 50 or 60 Hz (jumper selectable)

General

Features Specifications

Vari-Watt Power Controller

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Application Diagrams (Typical)

Single PhaseVoltage Supply

OptionalFusing

SSR #1

L1

T1

A2 (-)

A1 (+)

Variwatt (J3)

Load

8 7 6 5 4 3 2 1

Single PhaseVoltage Supply

OptionalFusing

SSR #4

L1

T1

A2 (-)

A1 (+)Load

SSR #2SSR #3(-) (+)(-) (+)

Typical 1-4 SSR’s

CustomerOutputs

Single PhaseVoltage Supply

OptionalFusing

SSR #1

L1

T1

A2 (-)

A1 (+)

Variwatt (J3)

Load

8 7 6 5 4 3 2 1 CustomerOutputs

Load

3-PhaseVoltage Supply

OptionalFusing

OptionalFusing

OptionalFusing

SSR #1

SSR #2

L1

L1

T1

T1

A2 (-)

A2 (-)

A1 (+)

A1 (+)

Variwatt (J3)8 7 6 5 4 3 2 1 Customer

Outputs

Single Phase Applicataion

3-Phase Phase Applicataion

Multiple OutputApplications Load Management

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Board Dimensions End View of DIN Rail Enclosure• 3.5x5.1” (90x130) Overall Dimensions

• Allow 2” (51) for circuit Board Height Above DIN Rail Enclosure

2.825(72)

1 2 3 4 5 6 7 8 1 2

1 2 3 4 5 6 7 8 1 2 3

J3 J2

J1 J6

U2

D1

R7

R35

R5

R1

R11

R34

C4

R18

R6

1J7

J3

U4

RV2

R14

C22

R3

1

R20

C6

R19

+

R9

U3

R36

C12

56 2

1

J9

F1

R13

C3

1

1

1

J1 1

C19

D10

R38

R39

R17

11

1

U2Q1

D1

R7

U5

C17

C9

R32

R35

R5

R1

R24 ~

~ -

+

D6

R11

C10

+

F2

Q3

R34

R28

C4

R18

D3T2

R22

R6

1J7

D7

D5

R8

1J3

RV1

U4

RV2

R14

U1

C22

1

U6

R3

1

R20

C6

R15

R19

Q4

RV3

C8

R2

C2+

C18

R10 R23

R9

U3

L1

R36

C12

C15

R25

C1

R31

56 2

1

J9

R16

C14

C20

R26

C5

C13

+

R4

F1

R13

R12

+

G

C11

Q2

1J2 R27

R21Q5

+C16

1

1

1

J1 J6

2AG

1/2A

250V

T1

1D2

D4

C19

R37D8D9D10

R38

D11

R39

R29R30

R33

14

5 8

+5V

R17

CHRO

MAL

OX IN

CVA

RIW

ATT B

OARD

J4

J5

F3J11

1J12

1J13

J101

C21

C7

RT1

5.0(127)

3.52(89.6)

1.99(46.5) 1.73

(44)

1.53(39)

Input Connections

4-20 mAdc Input

(-) (+)

4-20 mA

Variwatt (J1)

1 2 3 4 5 6 7 8

Variwatt (J1)

1 2 3 4 5 6 7 8

Manual Input10K Potentiometer

Jumper(4-5)

10KPotentiometer

Variwatt (J1)

1 2 3 4 5 6 7 8

Auto/Manual Selection

Open = AutoClosed = Manual

(-) (+)

Variwatt (J1)

1 2 3 4 5 6 7 8

0-5 Vdc, 0-10Vdc Inputs

0-5 Vdc0-10Vdc

+-

Description Number PCN

Vari-Watt Controller 0113-10237 339768

Potentionmeter (10K) 0135-27000 313947

Ordering Information

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See TableRemove J7 for 50 Hz Operation

See TableInput Jumper Selections(J10, J11, J12, J13)

(0 = Remove Jumper, X = Jumper Installed)

Input Type J10 J11 J12 J13 J7

4 - 20 mA DC X X X X N/A

0 - 5 Vdc 0 0 X 0 N/A

0 - 10 Vdc 0 0 0 0 N/A

50 Hz N/A N/A N/A N/A 0

60 Hz N/A N/A N/A N/A X

Jumper Selection Table

AC LINE

AC NEU

TRAL

EARTH G

RO

UN

D

[POT W

IPER IN

PUT]

AUTO

/ MAN

UAL CO

NTR

OL

AUTO

/ MAN

UAL CO

NTR

OL

ANALO

G IN

PUT - [O

UT TO

POT]

ANALO

G IN

PUT +

+5 VDC [O

UT TO

POT]

SSR

1 (R

TRN

)

SSR

2 (R

TRN

)

SSR

3 (R

TRN

)

SSR

4 (R

TRN

)

SSR

4 (+

12VD

C)

SSR

3 (+

12VD

C)

SSR

2 (+

12VD

C)

SSR

1 (+

12VD

C)

AUX

OU

T

AUX

OU

TCUSTOMER OUTPUTS

CUSTOMER INPUTS

AC POWER(90-250Vac, 50 or 60 Hz Selectable)

1 2 3 4 5 6 7 8 1 2

1 2 3 4 5 6 7 8 1 2 3

J3 J2

J6

Q1

D1

R7

U5

C17

C9

+

R32

R35

R5

R1

R24 ~

~ -

+D6

R11

C10

+

F2

Q3

R34

R28

C4

R18

-D3

T2

R22

R6

1J7

-

D7

D5

R8

1J3

RV1

U4

RV2

R14

U1

C22

1

U6

R3

1

R20

C6

R15

R19

Q4

C8

R2

C2+

C18

R10 R23

R9

U3

L1

R36

C12

R25

C1

R31

56 2

1

J9

R16C1

4

C20

R26

C5

C13

+

R4

F1

R13

R12

+

G

C11

C3Q2

1J2 R27

R21Q5

+C16

1

1

J1 1J6

2AG

1/2A

250V

T1

1

-

D2

-

D4

C19

R37D8D9D10

R38

R39

R29R30

R33

14

5 8

+5V

R17

CHRO

MAL

OX IN

CVA

RIW

ATT B

OARD

J4

J5

F3J11

1J12

1J13

J101

C21

C7

RT1

U2

1

RV3C15

1D11

1

J1

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Limited Warranty:Please refer to the Chromalox limited warranty applicable to this product at

http://www.chromalox.com/customer-service/policies/termsofsale.aspx.

© 2018 Chromalox, Inc. All rights reserved.

Chromalox103 Gamma Drive

Pittsburgh, PA 15238(412) 967-3800

www.chromalox.com