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which kind of relay should i use?

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JimLo

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could anybody tell me the differences among following relays:

PCB?

GP?

HF?

Solid Stat?

Low Signal?

MOS-FET?

typically , what are they used for???



if i just want a 3v signal to control a dual switch between two outputs using the relay, which should have low state-on resistance with peak current of 1 or 2A. could you tell me which kind of above relays should i use?

thank you very much for your help, my friend.
 

JimLo

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by the way, each output load is to drive a motor.

Peak current is around 1a~1.5a
 

IanP

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Assuming you are talking about dc motors, the MOSFET relay from your second PDF file seems to be the possible choice .. its continous current is 2A ..

The PCB relays from your second PDF file are just samll relays rated for mAs current, and are design for switching small signals (PCB applications) ..

GP --> general purpose

HF --> High frequency

Solid state ralay --> name reserved for AC switching at zero-crossing ( see: http://www.uoguelph.ca/~antoon/circ/solidstate.html )

Regards,
IanP
 

    JimLo

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JimLo

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IanP said:
Assuming you are talking about dc motors, the MOSFET relay from your second PDF file seems to be the possible choice .. its continous current is 2A ..

The PCB relays from your second PDF file are just samll relays rated for mAs current, and are design for switching small signals (PCB applications) ..

GP --> general purpose

HF --> High frequency

Solid state ralay --> name reserved for AC switching at zero-crossing ( see: h**p://www.uoguelph.ca/~antoon/circ/solidstate.html )

Regards,
IanP

THANK YOU, YOU ARE HELPFUL, 3 POINTS HAVE BEEN ADDED TO U.

emh... i think , the average current of my dc motor is low at around 50mA.. the starting peak current is over 1A.

so could the following pcb relay G6H-2 be the possible choice?

How do you think about it?

P.S. should the pin1 and pin10 of following DPDT relay be connected to Vcc and ground? or should they be left unconnected?

thank you very much again...
 

IanP

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The G6H is a nice little PCB relay, and, according to its data sheet has contact rating for dc operation 1A@30Vdc (see table below), so it is suitable for your application ..

Pins 1 and 10 are the control pins: pin 1 (+) --> 3V/6V/5V/12V .., pin 10 (-) --> 0V ..
The coil may be connected either way round ..
Relay coils produce brief high voltage 'spikes' when they are switched off and this can destroy transistors and ICs in the circuit. To prevent damage you must connect a protection diode (see example below) across the relay coil. Note, that this diode is connected 'backwards' so that it will normally not conduct ..

Regards,
IanP
 

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    JimLo

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JimLo

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thank you for helping me again.



could i ask

following silly question?

according to above diagram, could i know the pin connection of the relay?

plz see follow pic..

should PIN 1 be connected to the high voltage?

are all the pins connected right?

if so, any requirement for the input data Q or Q?

do the input data take control of the whole operation?

could you explain again

many thanks for being patient, i am really a newbie...:cry:
 

IanP

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One thing you have to be aware of is that neither transistor nor its base resistor are part of a relay; they are external components, and they help to drive a relay of TTL/CMOS circuits (example of a relay driven by a CMOS gate is attached) ..

Pins 1 and 10 can be connected either way, however, you can find some relays with the protective diode build-in, and then the (+) and (-) signs are important, so, in your case, leave (10) at the transistor side, and (1) connected to Vcc ..

Regards,
IanP
 

    JimLo

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