how to select a din rail power supply
DESCRIPTION
www.asi-ez.com Selecting a DIN Rail mounted Power Supply can be tough. In this presentation,you will find suggestions on what to look for when selecting a power supply for your application.TRANSCRIPT
What to Look for When Choosing a
Power Supply
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Automation Systems Interconnect
Safety, reliability, and power factor
correction are among the prime
considerations
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Safety
First One of the most fundamental and often overlooked purposes of a power supply is to provide isolation and therefore safety from a high-voltage (or dangerous) supply line
Reliability
3
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Q: What Affects the Reliability of a Power Supply?
A: - Average load rate- Vibration- Ambient Temperature
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Key issue is the amount of heat generated by the internal components
ASI Power Supply Designed with Excellent Ventilation toAvoid Overheating
Mean Time Between Failure (MTBF)
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some manufacturers have developed their own proprietary calculations for MTBF that produce higher values, it is best to compare only using the MTBF as defined in MIL-HDBK-217E
Power Factor Correction
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key performance element of a power supply
is its power factor
Power Factor
Correction
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There are two primary methods of power factor correction (PFC). The first method is the use of a simple coil at the input, and the second involves the use of a special electronic power-factor-correction circuit. The use of the coil is referred to as "passive" PFC and it typically produces a power factor of 0.7 to 0.8. The best use of the available energy with the least amount of conducted harmonics can be achieved with "active" PFC.
“Active” PFCActive PFC can produce a power factor greater than 95% and is most useful in
larger power supplies, 24 Vdc at 10 A and higher, since the conducted harmonics are directly proportional to the current load.
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Power Factor
Correction
Look for the power supply to also meet the EN 55011-B and EN55022-B specification for electrical emissions and EN 61000.3.2 regarding harmonic emissions conducted back on the main input lines.
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Power Factor
Correction
Surge Protection
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This built-in feature (up to 4 kV of protection) saves valuable panel space by not requiring an external suppressor
A good power supply is one that offers a minimum of 5%, and ideally 10% of overload protection.
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Short-circuit protection:- For Safety Purposes
- Saves time in powering up after a short circuit
has been detected
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Agency Approvals
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UL, CSA, and CE compliance marks are
evidence of passing several safety and
electrical emissions requirements
Agency Approvals
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The UL 508 listing offers the additional benefit of not requiring a power supply
rated for twice the intended use. Without UL 508, the power supply must be
derated by 50% in order for the control cabinet to also be UL 508 compliant.
Contact ASI
For More
Power Supply Information:
asi-ez.com
877-650-5160
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