1 Acme Electric Transformer Seminar
Aug 16, 2015
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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?