S-75 Switching Power Supply

Q: What is the difference between a contactor and a relay?

A contactor is built for switching power circuits repeatedly at high current, often with motor duty ratings (AC-3) and arc-suppressing chambers. A relay switches control signals at low current. In practice: contactor for the motor, relay in the control circuit that drives the contactor coil.

Q: How do I calculate the correct contactor size for a motor?

Use the motor's full-load current, apply the AC-3 rating for the operating voltage, and allow for the number of starts per hour. As a rule of thumb, the contactor's AC-3 rating should be at least equal to the motor FLC, then step up one frame if the duty is heavy.

Q: Do you supply the coil voltage I need?

Coil voltages are specified per order. Send the model number, coil voltage and frequency you require and we will confirm availability and lead time.

Q: Are auxiliary contacts included?

Base models come with the standard auxiliary contact configuration for that frame. Add-on auxiliary blocks and mechanical interlocks can be quoted with the contactor.

About the S-75 Switching Power Supply

The S-75 Switching Power Supply is part of the ELEHPD Switching Power Supply range. Low price and high reliability 105℃ output capacitor AC input power suitable for the world High efficiency and low operation temperature Soft-start current can reduce the AC input impact effectiely With short-circuit and owwerload protection 100% full-load burning test Installed with EMI filter,minimum wave ELEHPD manufactures and exports low voltage electrical products from Yueqing, Zhejiang, China, supplying distributors, panel builders, M&E contractors and OEM buyers worldwide.

Typical applications

Motor control centres and pump or fan starters
Machine building, conveyors, packaging and CNC equipment
HVAC control panels and building automation
Water treatment, irrigation and pumping stations
Panel retrofits replacing electromechanical control gear

How to specify the right Switching Power Supply

Size the contact rating for the inductive load, not just the resistive current (AC-3 duty for motors)
Check the coil voltage and frequency available in the panel: 24 V DC, 110 V, 230 V or 400 V AC
Confirm the auxiliary contact count needed for the control and indication circuit
Match the enclosure rating to the environment (IP20 inside a panel, IP65 on the machine)

Specifications

S-75 Switching Power Supply (Single Way)

Low price and high reliability

105℃ output capacitor

AC input power suitable for the world

High efficiency and low operation temperature

Soft-start current can reduce the AC input impact effectiely

With short-circuit and owwerload protection

100% full-load burning test

Installed with EMI filter,minimum wave

Model

Performance

S-75-5

S-75-12

S-75-15

S-75-24

DC output voltage

12V

15V

24V

Output voltage error(Note:2)

±2%

±1%

Rated output current

12A

2.8A

1.8A

Output current rage

0-15A

0-6.3A

0-5.0A

0-3.2A

Wave and noise(Note:3)

80mVp-p

100mVp-p

Inlet stability(Note:4)

±0.5%

±0.4%

±0.25%

Load stability(Note:5)

±1%

±0.5%

DC output power

75W

Efficiency

72%

77%

79%

780%

Adjustable range for DC voltage

+10%

±10%

Range for input votage

88~132VAC,170~264VAC,47~63Hz

Input current

15A/115V, 30A/230V

Impact current

Cool-start current 15A/115V, 30A/230V

Leakage current

<3.5mA/240VAC

Overload proctection

105%~150% TYPE:PULSING HICCUP SHUTDOWN RESET：reset:self-reset

Over-voltage protection

115%~135%

High-temperature protection

……

Temperature factor

±0.03%℃(0~50℃)

Start,rise and lock time

200ms,100ms,30ms/115VAC 200ms,100ms,30ms/230VAC

Vibration resistance

10~500Hz,2G 10min./1cycle,time60,minutes for each shaft

Resistance to pressure

Input and output internal:3KVAC,Input and enclosure:1.5KVAC,Output and enclosure:0.5KVAC

Insolationg resistance

Input and output internal,input and enclosure,Output and enclosure:500VAC/100M Ohms

Operating temperature and humidity

-10℃~+60℃，20%~90%RH

Store temperature and humidity

-20℃~+85℃,10%~95%RH

Overall dimension

159*97*38mm

Weight

0.52Kgs

Safety standard

Meet UL1012,TUV EN60950

EMC standard

Conform to IEC801-2,3,4,IEC555-2

Note:1.The testing condition for the paramenter above is :230VAC input,rated load, 25℃ 70% RH.Humidity
　　 2.Error.include the setting error,line stability and load stability.(Note:5)
　　 3.Wave test:adopting A12" double wire for 20MHz, and 0.1UF&47UF capacitor short-circuit for interrupting.
　　 4.Inlet voltage stability test:when is over load, the lowest voltage of inlet is up to the highest voltage.
　　 5.Load stability test:The load is from 0% to 100%
　　 6.C2,3,6 must be knocked down.

Frequently asked questions about the S-75 Switching Power Supply

What is the difference between a contactor and a relay?

A contactor is built for switching power circuits repeatedly at high current, often with motor duty ratings (AC-3) and arc-suppressing chambers. A relay switches control signals at low current. In practice: contactor for the motor, relay in the control circuit that drives the contactor coil.

How do I calculate the correct contactor size for a motor?

Use the motor's full-load current, apply the AC-3 rating for the operating voltage, and allow for the number of starts per hour. As a rule of thumb, the contactor's AC-3 rating should be at least equal to the motor FLC, then step up one frame if the duty is heavy.

Do you supply the coil voltage I need?

Coil voltages are specified per order. Send the model number, coil voltage and frequency you require and we will confirm availability and lead time.

Are auxiliary contacts included?

Base models come with the standard auxiliary contact configuration for that frame. Add-on auxiliary blocks and mechanical interlocks can be quoted with the contactor.