Mid-Continent Instrument True Blue Power TC234 Technical Document

Installation Manual and Operating Instructions
Model TC234
DC/DC Power Converter
True Blue Power®is a division of Mid-Continent Instrument Co., Inc.
Mid-Continent Instrument Co., Inc.
dba Mid-Continent Instruments and Avionics
9400 E. 34th Street N.
Wichita, KS 67226 Manual Number 9018670
PH [phone] FX [phone] Rev A, August 31, 2016

Rev A, August 31, 2016 2 Manual Number 9018670
FOREWORD
This manual provides information intended for use by persons who, in accordance with current
regulatory requirements, are qualified to install this equipment. If further information is required,
please contact:
True Blue Power
c/o Mid-Continent Instrument Co., Inc.
Attn: Customer Service Dept.
9400 E. 34th Street N.
Wichita, KS 67226 USA
PH [phone]
FX [phone]
www.truebluepowerusa.com
www.mcico.com
We welcome your comments concerning this manual. Although every effort has been made to
keep it free of errors, some may occur. When reporting a specific problem, please describe it
briefly and include the manual part number, the paragraph/figure/table reference and the page
number. Send your comments to:
True Blue Power
c/o Mid-Continent Instrument Co., Inc.
Attn: Technical Publications
9400 E. 34th Street N.
Wichita, KS 67226 USA
PH [phone]
FX [phone]
All products produced by Mid-Continent Instrument, Co., Inc., including those identified as Mid-
Continent Instruments and Avionics or True Blue Power, are designed and manufactured in
Wichita, KS, USA.
Copyright 2016
Mid-Continent Instrument Co., Inc.

Rev A, August 31, 2016 3 Manual Number 9018670
REVISION DETAIL
Revision
Date
Approved
Detail
A
08/31/16
SHO
Initial release

Rev A, August 31, 2016 4 Manual Number 9018670
TABLE OF CONTENTS
SECTION 1 GENERAL DESCRIPTION
1.1 INTRODUCTION 5
1.2 TECHNICAL SPECIFICATIONS 5
SECTION 2 INSTALLATION CONSIDERATIONS
2.1 COOLING 6
2.2 EQUIPMENT LOCATION 6
2.3 ROUTING OF CABLES 6
2.4 LIMITATIONS 6
SECTION 3 INSTALLATION PROCEDURE
3.1 GENERAL INFORMATION 7
3.2 UNPACKING AND INSPECTING 7
3.3 CABLE HARNESS 7
3.3.1 Wire Gauge Selection 7
3.3.2 Pin Assignment Information 7
3.3.3 Harness Verification 8
3.3.4 Output Voltage Adjustment 9
3.4 MOUNTING 10
3.5 INSTALLATION COMPLETION 10
3.6 INSTALL CAUTION 10
SECTION 4 OPERATION
4.1 ELECTRICAL PERFORMANCE 11
4.2 PROTECTIVE FEATURES 11
4.2.1 Remote On/Off 11
4.2.2 Input Under Voltage Limit 11
4.2.3 Over-Temperature 11
4.2.4 Short Circuit and Over-Current 11
SECTION 5 CONFORMANCE
5.1 CONTINUED AIRWORTHINESS STATEMENT 12
5.2 ENVIRONMENTAL QUALIFICATION STATEMENT 12

Rev A, August 31, 2016 5 Manual Number 9018670
SECTION 1 GENERAL DESCRIPTION
1.1 INTRODUCTION
The model TC234 DC/DC Power Converter is a lightweight power converter that translates a direct current
(DC) input of 14 volts to an output of 28 volts direct current (DC) output.
The input operating voltage (11-18 VDC) makes the TC234 suitable for nearly any common general,
business, or commercial aviation application. The unit is rated for a nominal output of 230 watts to power
avionics, instrumentation, personal charging, lighting, and many other applications. The TC234 DC/DC
Converter is FAA certified to TSO-C71 and tested to rigorous environmental standards and levels of
RTCA DO-160G. The small size and light weight in conjunction with its installation flexibility (inside or
outside the pressure vessel) make it an ideal choice for aircraft power needs while reducing the
challenges associated with other similar products.
Highlighted features include short circuit protection, overload capability, low input voltage shut-down,
temperature monitoring, reverse polarity protection, a self-resettable over-temperature disable and an
optional remote enable (on/off) feature.
The TC234 DC/DC converter has a robust Military-rated circular connector and a rugged aluminum case
which dissipates heat and provides excellent mechanical strength. It is engineered to require no external
cooling and contains no internal fans or cooling methods, which saves energy, reduces weight and allows
more flexible installation locations. At only 0.70 pounds, it is lighter and smaller than any other certified
solution in the aviation market today.
1.2 TECHNICAL SPECIFICATIONS
Electrical Attributes:
Model TC234
Input Voltage:
Rated 14VDC nominal, Operating 10 - 18VDC.
Input Current (full load):
18 amps max at nominal input voltage
Output Voltage
28VDC ± 3% adjustable
Output Current
Continuous 8 A, Max 9 A for 2 hr.
Output Power:
230 watts
Efficiency:
90% nominal
Table 1.1
Physical Attributes:
Model TC234
Weight:
0.70 lbs (0.32 kg)
Dimensions:
(not including connector mate)
2.75 inches long x 3.75 inches wide x 1.29 inches high
(69.85 mm long x 95.25 mm wide x 32.77 mm high)
Mating Connector (and cable clamp):
6430234-1
MCIA P/N 9018654
6430234-2
MCIA P/N 9018655
Mounting:
Base mount –orientation not critical
Table 1.2
Qualifications:
Model TC234
Certification:
FAA TSO-C71
Environmental Qualification:
RTCA DO-160G Environmental Category; See Section 5.2
Altitude:
-15,000 feet to +55,000 feet
Temperature:
-55°C to +70°C (-67°F to +158°F)

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Table 1.3
SECTION 2 PRE-INSTALLATION CONSIDERATIONS
2.1 COOLING
The TC234 product does not require external cooling or contain internal active cooling. Cooling of the unit
occurs exclusively through passive conduction through the base or radiated cooling across the metal
case. Additional cooling can be realized through convection (exposure to free moving air) or conduction
(mounting to a thermally conductive metal surface). These methods are not required to achieve rated
performance but can help prevent potential overheating and extend life when the unit is operated at full
power or during overload conditions. Specifically, mounting the unit to a metal surface is preferred, but
not required.
2.2 EQUIPMENT LOCATION
The TC234 is designed for mounting flexibility, allowing for installation inside or outside the pressure
vessel with no requirement for temperature control. In addition to altitude and temperature resistance, the
unit is also designed to withstand high levels of condensing humidity. However, installation locations
where the unit could be subject to standing or direct water exposure should be avoided. The unit can be
mounted in any orientation. Clearance should be provided for the mating connector and may require as
much as five inches past the unit connector to allow for back shell access to the connector.
2.3 ROUTING OF CABLES
The wires and cable bundle associated with the unit are heavy gauge wire and carry significant power. Be
aware of routing cables near other electronics or with other wire bundles that may be susceptible to high
energy flow.
Avoid sharp bends in cabling and routing near aircraft control cables. Also avoid proximity and contact
with aircraft structures, avionics equipment, or other obstructions that could chafe wires during flight and
cause undesirable effects.
2.4 LIMITATIONS
The TC234 contains an internal DC-to-DC conversion function to produce the rated output as
specified. This function meets the requirements of FAA TSO-C71. The TC234 also creates an
initial translation of a direct current (DC) input to the intermediate DC voltage, which then gets
converted to the rated output. This initial translation of DC-to-DC power is considered a non-TSO
function. This is due to the lack of an available DC-to-DC Technical Standard Order. However,
the DC-to-DC function is fully tested and verified per the equipment requirements and design as
well as the stated environmental requirements. The data to support the non-TSO function have
been submitted to and reviewed by the FAA along with the TSO-C71 requirements and
functionality.
The conditions and tests for TSO approval of this article are minimum performance standards. Those
installing this article, on or in a specific type or class of aircraft, must determine that the aircraft installation
conditions are within the TSO standards. TSO articles must receive additional installation approval prior
to being operated on each aircraft. The article may be installed only according to 14 CFR Part 43 or the
applicable airworthiness requirements.

Rev A, August 31, 2016 7 Manual Number 9018670
SECTION 3 INSTALLATION PROCEDURES
3.1 GENERAL INFORMATION
This section contains interconnect diagrams, mounting dimensions and other information pertaining to the
installation of the TC234 DC/DC Converter. After installation of cabling and before installation of the
equipment, ensure that power is applied only to the pins specified in the interconnect diagram.
The following two versions of the unit are available. See section 4.2.1 for additional details of the remote
enable (on/off) feature and installation details within section 3.
Part Number
Remote On/Off
6430234-1
No (output always enabled)
6430234-2
Yes (enable signal required)
3.2 UNPACKING AND INSPECTING EQUIPMENT
When unpacking this equipment, make a visual inspection for evidence of any damage that may have
incurred during shipment. The following parts should be included:
a. DC/DC Converter MCIA P/N 6430234-( )
b. Mating Connector (& cable clamp)
a. 6430234-1 MCIA P/N 9018654
b. 6430234-2 MCIA P/N 9018655
c. Installation Manual MCIA P/N 9018670
Equipment not provided:
a. Mounting Hardware four 6-32 pan head screws
#6 lock washers (optional)
b. Cable Harness Wire See Section 3.3 for specifications
3.3 CABLE HARNESS
Construct the cable harness with regards to the instructions below, and using Figures 3.1 –3.6, and
Wiring Diagram of Table 3.3 and 3.4.
Refer to Section 2: Pre-Installation Considerations in regards to routing precautions.
3.3.1 Wire Gauge Selection
Use of PTFE, ETFE, TFE, Teflon, or Tefzel insulated wire is recommended for aircraft use.
Use the following wire gauges for each of the pins in the connector:
Pins A –14AWG stranded or solid
Pins B and C –14 AWG or 16 AWG stranded or solid
Pins D –24 AWG stranded or solid
3.3.2 Pin Assignment Information
Positive DC input –(11 -18 VDC). Connect pin A to aircraft positive 14 VDC bus.

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(25 Amp circuit breaker recommended)
DC Output –Connect pin C as the positive 28V DC output voltage.
DC Return –Connect pin B to input power return or aircraft ground.
Enable –6430234-1: Not available
6430234-2: Pin D to be grounded to enable power output
(via switch or other means. See section 4.2.1 and figure 3.6 for related details)
Figure 3.3 Table 3.3
Pinout View of 6430234-1 Unit Connector 6430234-1 Connector Pinout
Figure 3.4 Table 3.4
Pinout View of 6430234-2 Unit Connector 6430234-2 Connector Pinout
3.3.3 Harness Verification
With the TC234 Static Converter disconnected, activate the aircraft power bus that supplies
the unit and use a multi-meter to verify that aircraft power and ground with appropriate
voltage is on the pins within the mating harness.
Connector Pinout
A
DC Power Input
B
DC Power Return
C
DC Power Output
Connector Pinout
A
DC Power Input
B
DC Power Return
C
DC Power Output
D
Remote ON/OFF

Rev A, August 31, 2016 9 Manual Number 9018670
(Update to TC234 and 6430234-1)
A
B
C
DC INPUT
TC234
6430234-1 DC OUTPUT
DC RETURN
Figure 3.5: Typical 6430234-1 Aircraft Wiring Installation –Constant On
(Update to TC234 and 6430234-2)
D
DC OUTPUTC
DC RETURN
B
ADC INPUT
ENABLE
TC234
6430234-2 ON
OFF
ON/OFF
Figure 3.6: Typical 6430234-2 Aircraft Wiring Installation –Remote On/Off

Rev A, August 31, 2016 10 Manual Number 9018670
3.4 MOUNTING
Refer to Section 2: Pre-Installation Considerations in regards to equipment location.
The TC234 DC/DC Converter is designed for base mounting only. Four 6-32 mounting holes should be
provided in the aircraft in accordance with Figure 3.7. Secure the unit with four 6-32 pan head screws, or
equivalent. A lock washer under the head of each screw is recommended.
1.29
3.75 Connector per
MS3102A-16-10P
6430234-1
2.75
2.40
0.75
3.38
4X Ø.15 Mounting Holes for
#6-32 X 1.0" (min)
Connector per
MS3102A-16-9P
6430234-2
Figure 3.7
TC234 DC/DC Converter Outline Drawing
3.5 INSTALLATION CAUTION
Under no circumstances should the output of the Converter to be connected to another power output
source or damage will occur to the unit or the connected power source.
3.6 INSTALLATION COMPLETION
Prior to operating the unit in the aircraft, it is recommended to verify the output and functionality of the
unit. In order to prevent accidental damage to other systems, it is best not to attach the output to other
equipment or power busses prior to verification. Verify the output of the unit at the terminating end of the
cable with a multi-meter to ensure proper voltage and polarity. Once verified, installation can be
completed and functionality of the remote on/off feature (if used) should be checked.

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SECTION 4 OPERATION
4.1 ELECTRICAL PERFORMANCE
The TC234 is designed as a non-isolated, boost topology, solid-state switch-mode power supply. The unit
converts a direct current voltage (11-18VDC) input to a regulated 28 VDC output. It is capable of
providing up to 252 watts of power to a variety of aircraft accessories including lights and onboard
systems or portable consumer product power. Rated output 8A is for free standing continuous but output
can go up to 10A if the unit is mounted to a metal surface.
4.2 PROTECTIVE FEATURES
4.2.1 Remote On/Off
The TC234 DC/DC Converter (6430234-2 only) incorporates a remote on/off feature that
allows the user to enable or disable the output of the unit. By providing a ground on the
appropriate pin the user, via a remote mounted switch, can enable the output of the unit. (See
Figure 3.6)
4.2.2 Input Under Voltage Limit
If the input voltage drops below 11 VDC the unit senses an under-voltage condition and
disables the output.
4.2.3 Over-Temperature
The TC234 DC/DC Converter incorporates an internal temperature sensing device that
continually provides monitoring and feedback to the control circuits. When the unit senses an
internal condition that exceeds maximum temperature ratings, the output is disabled. The
Converter will continue to remain shut-down until the temperature returns to within acceptable
limits. This over-temperature reset occurs automatically without external intervention
required.
4.2.4 Short Circuit And Over-Current
The TC234 DC/DC Converter is capable of surviving a short circuit or over-current event
without permanent damage or effect to long-term reliability. The unit can provide over its
rated power output up to 252 watts for over 120 minutes (until over-temperature shutdown
occurs).
The Converter monitors the DC output on a pulse-by-pulse scenario to determine a short -
circuit or over-current situation. If detected, the output is limited by limiting the current output
to less than 10A. The short-circuit condition is latched until power is cycled off and back on.

Rev A, August 31, 2016 12 Manual Number 9018670
SECTION 5 CONFORMANCE
5.1 INSTRUCTIONS FOR CONTINUED AIRWORTHINESS
No periodic scheduled maintenance or calibration is necessary for continued airworthiness of the
TC234 DC/DC Converter. If the unit fails to perform to specifications, the unit must be removed and
serviced by Mid-Continent Instruments and Avionics or their authorized designee.
5.2 ENVIRONMENTAL QUALIFICATION STATEMENT
PART NUMBER : 6430234
MODEL NUMBER : TC234
NOMENCLATURE : DC/DC Converter
TSO NUMBER : C71
MANUFACTURERS SPECIFICATIONS: Test Specification (TS) 700-(P), Test Data Sheet (TDS) 700-(P)
QUALIFICATION STANDARD : RTCA DO-160G
CONDITIONS
SECTION
DESCRIPTION OF TEST
Temperature and Altitude
Low Temperature
High Temperature
Decompression
Overpressure
4
4.5.1
4.5.3
4.6.1
4.6.2
4.6.3
Category F2
Operating Low Temp = -55C
Operating High Temp = +70C
Altitude = +55,000 ft.
+8,000 to +55,000 ft.
-15,000 ft.
Temperature Variation
5
Category S2
Humidity
6
Category B
Operational Shock and
Crash Safety
7
Category B
Vibration
8
Category R; Curve C, C1 [(RCC1)]
Explosion
9
Category X
Waterproofness
10
Category X
Fluids
11
Category X
Sand and Dust
12
Category X
Fungus
13
Category F
Salt Spray
14
Category X
Magnetic Effect
15
Category Z
Power Input
16
Category B(XX)
Voltage Spike
17
Category B
Audio Frequency Conducted
Susceptibility
18
Category R
Induced Signal Susceptibility
19
Category X
Radio Frequency Susceptibility
20
Category X
Emission of Radio Freq Energy
21
Category M
Lightning Induced Transient
Susceptibility
22
Category X
Lightning Direct Effects
23
Category X
Icing
24
Category X
ESD
25
Category A
Flammability
26
Category X

Rev A, August 31, 2016 13 Manual Number 9018670