transformer seminar - buck-boost

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Acme ElectricTransformer Seminar

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“BUCK-BOOST”

APPLICATIONS

Transformer Seminar

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What are BUCK-BOOST TRANSFORMERS?

BUCK-BOOST TRANSFORMERS START OUT AS ISOLATION TRANSFORMERS WITH OUTPUTS FROM 12 TO 48 VOLTS, WHICH GET FIELD CONNECTED AS “AUTO” TRANSFORMERS TO INCREASE OR DECREASE VOLTAGE WITHIN A RANGE OF 5 TO 20 PERCENT. (ie, 208 T0 230 V)

THEY DO NOT PROVIDE ISOLATION FROM THE SUPPLY BECAUSE THEY ARE “AUTO” CONNECTED DURING INSTALLATION!

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PRIMARY SECONDARY

AUTOISOLATION

“Isolation” vs. “Auto”

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BASIC PRINCIPLE

CURRENT WILL FOLLOW PATH OF LEAST RESISTANCE

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PRIMARY & SECONDARY have the same CAPACITY

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BOOSTING CONNECTION COIL VOLTAGES ADD

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AUTO CONNECTION INCREASES KVA CAPACITY

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DATA needed to SELECT BUCK-BOOST TRANSFORMER

1. SYSTEM PHASE2. SYSTEM FREQUENCY3. LINE VOLTAGE4. LOAD VOLTAGE5. LOAD KVA, AMPS, OR HORSEPOWER

(Available line voltage should be measured whenever possible)

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SELECTION EXAMPLE #1

1. 1-PHASE2. 60 HZ3. LINE - 189 VOLTS4. LOAD - 208 VOLTS5. LOAD - 4 KVA

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1-PHASE GROUP I CHART

REFER TO 1-PHASE GROUP I SELECTION CHART IN SECTION VII OF CATALOG ATD-01.

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CONNECTION DIAGRAM

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SELECTION EXAMPLE # 2

1. 1 - PHASE2. 60 HZ3. LINE - 208 VOLTS4. LOAD - 240 VOLTS5. LOAD - 60 AMPS

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1-PHASE GROUP II CHART

REFER TO 1-PHASE GROUP II SELECTION CHART IN SECTION VII OF CATALOG ATD-01.

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CONNECTION DIAGRAM

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SELECTION EXAMPLE # 3

1. 1 - PHASE2. 60 HZ3. LINE - 240 VOLTS4. LOAD - 208 VOLTS5. LOAD - 14 KVA

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1-PHASE GROUP II CHART

REFER TO 1-PHASE GROUP II SELECTION CHART IN SECTION VII OF CATALOG ATD-01.

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CONNECTION DIAGRAM

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SELECTION EXAMPLE # 4

1. 3 - PHASE2. 60 HZ3. LINE - 208 VOLTS4. LOAD - 230 VOLTS5. LOAD - 80 KVA

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3-PHASE GROUP I CHART

REFER TO 3-PHASE GROUP I SELECTION CHART IN SECTION VII OF CATALOG ATD-01.

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Connection Diagram B-B

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BUCK-BOOST SLIDE CHART

DEMONSTRATE SLIDE CHART

(No longer available)

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TYPICAL APPLICATIONS for BUCK-BOOST TRANSFORMERS

1. AIR CONDITIONERS2. AC MOTORS3. PUMPS4. TANNING BEDS (No. 1 application)5. CONTROL CIRCUITS

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GENERAL APPLICATION COMPARISONSTANDARD ISOLATION TRANSFORMER

Handle large increases or decreases in voltageProvide electrical isolation and shielding if required

BUCK-BOOST TRANSFORMERSHandle small increases or decreases in voltage (+/-

5 to 20%)Do not provide electrical isolation (because they

get “auto” connected)

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Effects of LOW VOLTAGE on MOTOR OPERATION

VOLTAGE CURRENT TEMPERATURE- 5 % + 5 % + 11 %

- 10 % + 11 % + 23 %

- 15 % + 17 % + 38 %

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• DETERIORATE INSULATION• NUISANCE TRIPPING OF BREAKERS• INSUFFICIENT MOTOR TORQUE• WASTED ENERGY AND MONEY

Effects of LOW VOLTAGE on MOTOR OPERATION

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Effects of LOW VOLTAGE on MOTOR TORQUE

% RATED VOLTS % RATED TORQUE

100% 100% 90% 81%

80% 64%

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Causes of VOLTAGE MISMATCH

• SERVICE VOLTAGE CHANGED AFTER EQUIPMENT INSTALLED

• VOLTAGE DROP IN POWER LINE

• ERRORS IN ORDERING EQUIPMENT

• UTILITY CUTBACK IN SOURCE VOLTAGE

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GENERAL SIZE COMPARISON

STANDARD ISOLATION TRANSFORMER• 16”H X 14”W X 11”D 125 LBS• 1O KVA RATING

BUCK-BOOST TRANSFORMER• 10”H X 6”W X 5”D 24 LBS• 1 KVA RATING

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ACME BUCK-BOOST FEATURES

• UL LISTED/CSA CERTIFIED• UL 3R ENCLOSURES• ALLOWABLE UNDER NEC• EPOXY ENCAPSULATED• (EXCEPT 50, 100, 150 VA)• BROAD RANGE OF VOLTAGES • TEN YEAR WARRANTY

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Buck Boost Hands-On LabIn this exercise we will wire a typical Buck-Boost transformer for the following

applications:

Input Output Diagram Connection Type 120v 12v K Isolation 120v 24v L Isolation 240v 12v M Isolation 240v 24v N Isolation 120v 132v C Auto 120v 144v D Auto 120v 100v D Auto (reverse input & output)

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Buck Boost “Isolation” Diagrams

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Buck Boost “Auto” Diagrams

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Buck Boost Hands-On LabIn this exercise we will wire a typical Buck-Boost transformer for the

following applications:

Input Output Diagram Connection Type 120v 12v K Isolation120v 24v L Isolation240v 12v M Isolation240v 24v N Isolation120v 132v C Auto120v 144v D Auto120v 100v D Auto (reverse input & output)

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Buck Boost “Isolation” Diagrams

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Buck Boost “Auto” Diagrams

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Questions?