SPECIFICATIONS
Part Number: IC3600EPSM1
Manufacturer: General Electric
Series: Mark I and II
Function: Power Supply Converter
Repair: 3-7 Day
Technology: Surface-mount
Availability: In Stock
Country of Manufacture: United States (USA)
Functional Description
IC3600EPSM1 is a Power Supply Converter manufactured and designed by General Electric. It is a part of the Mark I and II Control System. This 75-watt power supply converter delivers stable, filtered 12V and 28V DC outputs to support downstream regulators and critical control modules.
Features
- The Converter is responsible for converting a 105V to 135V DC input into unregulated DC bus voltages. These unregulated buses serve as the foundation for regulated outputs (12V and 28V), managed by the Final Regulators, including the 12V, 2SV Regulator module.
- The converter can also be configured as an unregulated 28V, 2A supply to power auxiliary loads such as indicator lights or control relays. In this configuration, the 28V output bus voltage scales directly with the input voltage level.
Circuit Operation
- Startup Sequence: When SW1 is closed into a 135V DC source, polarity verification is critical. An incorrect polarity will trigger CR10, blowing the 1A fuse FU1 for safety. Correct polarity allows current to flow via the R8-C6 network into Q1’s base, causing it to saturate and initiate oscillation.
- Self-Oscillating Inverter Operation: Q1 is kept in saturation by its base winding until the square-loop transformer T1 saturates. Upon transformer saturation, collector current rises, activating R27 and R28, causing Q1 to cut off. This transformer reset action triggers Q2 to turn on, maintaining the oscillation cycle. The inverter runs at a frequency of approximately 1 kHz, alternating between Q1 and Q2 conduction.
- AC to DC Conversion and Filtering: T1’s secondary windings provide AC square wave outputs. Full-wave bridges (CR11, CR12, and CR1–CR4) rectify the AC into DC voltage levels. Capacitors C10–C12 filter the DC outputs to ensure smooth voltage delivery.
Protection Mechanisms
- Spike Suppression: R-C snubber networks (C3-R20 and C2-R21) suppress voltage spikes due to transformer leakage inductance.
- Line Ringing Prevention: Capacitor C8 mitigates line ringing from high-speed switching events.
- Overload Protection: FU2 provides overload protection when used as a relay supply. In regulated power supply mode, current limiting is integrated into each regulated output, eliminating the need for external fuses.
- Short Circuit Protection: The converter is inherently short-circuit-proof. A short at the output reflects back to the base windings, halting the inverter by cutting off base drive. Q3, a unijunction transistor oscillator, attempts inverter restart every 0.5 seconds. Under normal conditions, Q3 does not pulse due to the inverter's higher operating frequency preventing capacitor C4 from charging.
Input Specifications
- DC Voltage Input: 105V to 135V at 1A.
- Wiring Recommendation: Use twisted wire pairs to reduce inductance and ensure noise immunity.
Output Options
- Relay/Light Bus Mode: 28V Unregulated DC Output at up to 2 Amps. Short-Circuit Protected via automatic inverter shutdown.
- Overload Protection: Provided by a 3A fuse.
- Test Jacks: Built-in for convenient monitoring of the 28V bus voltage.
WOC is happy to assist you with any of your automation requirements. For pricing and availability on any parts and repairs, contact us.
FREQUENTLY ASKED QUESTIONS
What is IC3600EPSM1?
It is a Power Supply Converter manufactured and designed by General Electric.
What is the input voltage range for the module?
The converter operates with an input DC voltage range of 105 to 135 volts.
What are the output capabilities of this power supply converter?
It provides unregulated 28V DC output at 2 amps, suitable for driving lights and relays, and filtered outputs for use with 12V and 28V regulators.
Is the module protected against short circuits?
Yes, it includes built-in short circuit protection. A short circuit on the output causes the inverter to shut off automatically and retry every 0.5 seconds via a unijunction oscillator circuit.
Does the converter include overload protection?
Yes. Overload conditions are managed with a 3A fuse for relay bus applications. Additionally, each regulated supply in the system has its current limit.
What is the typical switching frequency of the inverter circuit?
The internal inverter circuit operates at approximately 1 kHz.
