Relay
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Posts: 46,084
I want to use an output on the stamp to activate the relay (see specs
below). is this relay safe to use without any additional circuitry to reduce
the current? the relay will switch 120vac on and off. I have a 12vdc power
supply delivering power to the stamp. all but two I/O's are in use. if I
need to add resistors or something else can someone please tell me what I
need.
also:
what does reverse voltage mean?
this relay will be turning on then off about once per second, will i need a
heat sink or anything like that?
Thanks for the help.
---
SPST Solid State Relay
(275-0310) Specifications Faxback Doc. # 18859
Absolute Maximum Ratings:
Input:
Forward Current: ................................................... 50 mA
Reverse Voltage: ..................................................... 6 V
Output:
RMS On-state Current: ........................................... 3 A(RMS)
Peak One Cycle Surge Current: ....................................... 30 A
Repetitive Peak Off-state Voltage: ................................. 400 V
Non-repetitive Peak Off-state Voltage: ............................. 400 V
Critical Rate of Rise of On-state Current: ............. 40 A/micro-second
Operating Frequency: ......................................... 45 to 65 Hz
Operating Temperature: ............................. -25 to +100 Degrees C
Storage Temperature: ............................... -30 to +125 Degrees C
Isolation Voltage: ........................................... 3.0 kV(RMS)
Soldering Temperature: ..................... 260 Degrees C(For 10 Seconds)
Electrical Characteristics:
Input:
Forward Voltage: ................................ 1.2 V (Typ.); 1.4 V(Max)
Reverse Current: ..................................... 10 to -4 Power Amps
Output:
Repetitive Peak Off-state Current: ................... 10 to -4 Power Amps
On-state Voltage: ............................................. 1.5 V(RMS)
Holding Current: ................................................... 50 mA
Critical Rate of Rise of Off-state Voltage: .......... 30 V/micro-sec(Min)
Commutation Critical Rate of Rise of Off-state Voltage: 4 V/micro-sec(Min)
Transfer Characteristics:
Minimum Trigger Current: ........................................... 15 mA
Isolation Resistance: .......................... 10 to the 10th power Ohms
"Latch Time", Momentary, Turn On Time: ................... 1 ms @ 50 Hz AC
Turn Off Time: .......................................... 10 ms @ 50 Hz AC
Thermal Resistance Between Junction Case: ............... 6 Degrees C/Watt
Thermal Resistance Between Junction Ambient: ........... 45 Degrees C/Watt
Dimensions (HWD): ............................. 1.375 x .75 x .1875 Inches
(34.9 x 19 x 4.75 mm)
below). is this relay safe to use without any additional circuitry to reduce
the current? the relay will switch 120vac on and off. I have a 12vdc power
supply delivering power to the stamp. all but two I/O's are in use. if I
need to add resistors or something else can someone please tell me what I
need.
also:
what does reverse voltage mean?
this relay will be turning on then off about once per second, will i need a
heat sink or anything like that?
Thanks for the help.
---
SPST Solid State Relay
(275-0310) Specifications Faxback Doc. # 18859
Absolute Maximum Ratings:
Input:
Forward Current: ................................................... 50 mA
Reverse Voltage: ..................................................... 6 V
Output:
RMS On-state Current: ........................................... 3 A(RMS)
Peak One Cycle Surge Current: ....................................... 30 A
Repetitive Peak Off-state Voltage: ................................. 400 V
Non-repetitive Peak Off-state Voltage: ............................. 400 V
Critical Rate of Rise of On-state Current: ............. 40 A/micro-second
Operating Frequency: ......................................... 45 to 65 Hz
Operating Temperature: ............................. -25 to +100 Degrees C
Storage Temperature: ............................... -30 to +125 Degrees C
Isolation Voltage: ........................................... 3.0 kV(RMS)
Soldering Temperature: ..................... 260 Degrees C(For 10 Seconds)
Electrical Characteristics:
Input:
Forward Voltage: ................................ 1.2 V (Typ.); 1.4 V(Max)
Reverse Current: ..................................... 10 to -4 Power Amps
Output:
Repetitive Peak Off-state Current: ................... 10 to -4 Power Amps
On-state Voltage: ............................................. 1.5 V(RMS)
Holding Current: ................................................... 50 mA
Critical Rate of Rise of Off-state Voltage: .......... 30 V/micro-sec(Min)
Commutation Critical Rate of Rise of Off-state Voltage: 4 V/micro-sec(Min)
Transfer Characteristics:
Minimum Trigger Current: ........................................... 15 mA
Isolation Resistance: .......................... 10 to the 10th power Ohms
"Latch Time", Momentary, Turn On Time: ................... 1 ms @ 50 Hz AC
Turn Off Time: .......................................... 10 ms @ 50 Hz AC
Thermal Resistance Between Junction Case: ............... 6 Degrees C/Watt
Thermal Resistance Between Junction Ambient: ........... 45 Degrees C/Watt
Dimensions (HWD): ............................. 1.375 x .75 x .1875 Inches
(34.9 x 19 x 4.75 mm)
Comments
I looked at your specs and Radio Shack specs, and would not use this part
because it is not adequately specified regarding the input circuit. Digikey
sells solid state relays that are $4 to $10 that are specified to run a 2
amp load at 25 deg C without heat sinking. A good choice would be a relay
that can be driven directly from 5 volts without an external resistor, and
will require only ~5ma. input current. Keep in mind that they have a
minimum load current to operate properly, typically 100 ma. I think the
reverse voltage they are talking about for your part is input reverse
voltage, which is no concern with a stamp that outputs ~ 0 to 5v.
Ray McArthur
Original Message
From: Jason W. Day <dayjw@e...>
To: <basicstamps@egroups.com>
Sent: Monday, April 24, 2000 3:58 PM
Subject: [noparse][[/noparse]basicstamps] Relay
>
>
> I want to use an output on the stamp to activate the relay (see specs
> below). is this relay safe to use without any additional circuitry to
reduce
> the current? the relay will switch 120vac on and off. I have a 12vdc
power
> supply delivering power to the stamp. all but two I/O's are in use. if I
> need to add resistors or something else can someone please tell me what I
> need.
>
> also:
> what does reverse voltage mean?
> this relay will be turning on then off about once per second, will i need
a
> heat sink or anything like that?
The input is commonly 3 to 32 volts DC which your Stamp may control
directly. The output is optically isolated from the input.
I have found Hosfelt (http://www.hosfelt.com ) to be a good source of these.
I note they have one rated at 10A output @ 24 to 600 VAC. The Hosfelt # is
45-647. The price is $9.95.
These pucks lend themselves to mounting in a common electrical box which are
inexpensive and readily available from your local hardware store. I suggest
you take the time to do this and fully cover the box such that there is no
exposed AC. 120VAC will not only damage your Stamp. It can do a job on you
as well.
BTW. I have a lot of basement lights that my family seems to always leave
on. Rather than run AC wiring to the top of the stairs, I put one of these
pucks near each light and then ran low voltage pairs to the top of the
stairs and use small toggle switches to turn the lights on and off.
Peter H. Anderson, Morgan State University
pha@p..., http://www.phanderson.com
Homebrew Basic Stamps, Basic Stamp Starter Packages
Original Message
From: Jason W. Day <dayjw@e...>
To: basicstamps@egroups.com <basicstamps@egroups.com>
Date: Monday, April 24, 2000 3:56 PM
Subject: [noparse][[/noparse]basicstamps] Relay
:
:
: I want to use an output on the stamp to activate the relay (see specs
:below). is this relay safe to use without any additional circuitry to
reduce
:the current? the relay will switch 120vac on and off. I have a 12vdc
power
:supply delivering power to the stamp. all but two I/O's are in use. if I
:need to add resistors or something else can someone please tell me what I
:need.
:
[noparse]:also:[/noparse]
:what does reverse voltage mean?
:this relay will be turning on then off about once per second, will i need
a
:heat sink or anything like that?
:
:Thanks for the help.
:
:
-
:---
:
:
:
:SPST Solid State Relay
[noparse]:([/noparse]275-0310) Specifications Faxback Doc. # 18859
:
:Absolute Maximum Ratings:
:
:Input:
:
:Forward Current: ................................................... 50 mA
:
:Reverse Voltage: ..................................................... 6 V
:
:Output:
:
:RMS On-state Current: ........................................... 3 A(RMS)
:
:Peak One Cycle Surge Current: ....................................... 30 A
:
:Repetitive Peak Off-state Voltage: ................................. 400 V
:
:Non-repetitive Peak Off-state Voltage: ............................. 400 V
:
:Critical Rate of Rise of On-state Current: ............. 40 A/micro-second
:
:Operating Frequency: ......................................... 45 to 65 Hz
:
:Operating Temperature: ............................. -25 to +100 Degrees C
:
:Storage Temperature: ............................... -30 to +125 Degrees C
:
:Isolation Voltage: ........................................... 3.0 kV(RMS)
:
:Soldering Temperature: ..................... 260 Degrees C(For 10 Seconds)
:
:Electrical Characteristics:
:
:Input:
:
:Forward Voltage: ................................ 1.2 V (Typ.); 1.4 V(Max)
:
:Reverse Current: ..................................... 10 to -4 Power Amps
:
:Output:
:
:Repetitive Peak Off-state Current: ................... 10 to -4 Power Amps
:
:On-state Voltage: ............................................. 1.5 V(RMS)
:
:Holding Current: ................................................... 50 mA
:
:Critical Rate of Rise of Off-state Voltage: .......... 30 V/micro-sec(Min)
:
:Commutation Critical Rate of Rise of Off-state Voltage: 4 V/micro-sec(Min)
:
:Transfer Characteristics:
:
:Minimum Trigger Current: ........................................... 15 mA
:
:Isolation Resistance: .......................... 10 to the 10th power Ohms
:
:"Latch Time", Momentary, Turn On Time: ................... 1 ms @ 50 Hz AC
:
:Turn Off Time: .......................................... 10 ms @ 50 Hz AC
:
:Thermal Resistance Between Junction Case: ............... 6 Degrees C/Watt
:
:Thermal Resistance Between Junction Ambient: ........... 45 Degrees C/Watt
:
[noparse]:D[/noparse]imensions (HWD): ............................. 1.375 x .75 x .1875 Inches
: (34.9 x 19 x 4.75 mm)
:
:
:
:
my BS2 so the stamp can control it, but it doesn't work. What am I
doing wrong? It's probably something really easy I've overlooked, but
any help would be appreciated. Thanks.
>I have a 1.5vdc coil, 12 ohm, 120vac relay that I tried hooking up to
>my BS2 so the stamp can control it, but it doesn't work. What am I
>doing wrong? It's probably something really easy I've overlooked, but
>any help would be appreciated. Thanks.
Directly connected to the Stamp? If so, do the Ohm's Law calculations and
you'll see that that 12 ohm coil wants 125 ma at 1.5 volts and will ask for
417 ma at 5 volts. The Stamp can't provide that sort of drive. Look in
the Stamp manual (mine is loaned out at the moment) for how to connect the
relay using a transistor and a separate source of power.
Jim H
Keep in mind that if the coil is 12 ohms, sending 5V through the coil will
attempt to draw about 417mA (5/12). That's way too much. Also, relays need a
diode across the coil in reverse to short circuit voltage spikes caused by
changing the voltage in an inductor.
You can find an article about this in the Stamp FAQ at
http://www.al-williams.com/wd5gnr/stampfaq.htm
The short answer is to take, say, a 1K resistor and tie it to the Stamp pin.
Tie the other end to the base of a 2N2222 (NPN bipolar transistor). Tie the
emitter of the transistor to ground. The collector goes to the relay coil
(either side). The other side of the coil goes to a 1.5V supply. Put a small
diode (1N914 should be OK or a 1N4001) with the banded end toward the 1.5V
supply and the non-band end to the collector of the transistor. That will do
it.
Regards,
Al Williams
AWC
* Connect your Stamp to the Internet:
http://www.al-williams.com/awce/netporter.htm
>
Original Message
> From: sjohns10@h... [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=Tn3-fzJcl7MQhCrClMkP6sc8jfbdmDi19rBYdOv_gZNIuuwaZRXHS_ZC6Jt8bQ2MVGAWhE6Fxwr875Zc6s7v]sjohns10@h...[/url
> Sent: Thursday, May 24, 2001 5:56 PM
> To: basicstamps@yahoogroups.com
> Subject: [noparse][[/noparse]basicstamps] Relay
>
>
> I have a 1.5vdc coil, 12 ohm, 120vac relay that I tried hooking up to
> my BS2 so the stamp can control it, but it doesn't work. What am I
> doing wrong? It's probably something really easy I've overlooked, but
> any help would be appreciated. Thanks.
>
>
>
>
> Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
>
> my BS2 so the stamp can control it, but it doesn't work. What am I
> doing wrong? It's probably something really easy I've overlooked, but
> any help would be appreciated. Thanks.
Are you using a driver of any form ???? Most pins on any chip just cannot
drive that low a load.
Does this list allow attachments ???? I can very quickly sketch up a
driver. It takes a few extra components, but it would work .... (BTW - a
4.5V coil would make your life a little easier if you aren't married to that
one [noparse]:)[/noparse]....
John
<><><><><><><><><><><><><><><><><><><><>
John Ledford, Design Engineer
Instrumentation Design Laboratory
The University of Kansas
6042 Malott Hall, Lawrence, Kansas 66045
Office: (785) 864-4083
Fax: (785) 864-5396
http://www.idl.ku.edu
jledford@k...
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