Subject: From: Date:

Re: [ECS] Power Sentry & Secu 16 joerut.epix.net Wed, 17 Jan 2001 15:04:16 -0500 (EST)

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 Wed, 17 Jan 2001 15:04:16 -0500 (EST)
Doug 

One suggestion for replacing the relay is an optoisolator. This could have
2 benefits

1. All solid state. No MOVING parts or contacts to wear out.

2. Provides Isolation between the Secu16 and the power sentry.

I almost always use an optoisolator when connecting items to my system. It
removes the worries of some OTHER item creating noise on DC lines that
could cause problems for the digital inputs

One other note. I was also looking for a good CHEAP way to monitor my
power consumption. After seeing your post about the Power sentry I dug through
my huge box of used optic sensors and found an Omron sensor that will work
the same as the Power Sentry. I have tested it a bit and it seems very
reliable. I will glue it on when it gets a bit warmer. I am not sure of the
price of this sensor.

Later
Joe Rut


> Thanks you got me on the right track with the one shot.
> However the way I solved it is with a modified oneshot where the power
> sentry is the control voltage to a 555 timer. The output from this
circuit
> was tied to a reed relay (Power sentry will not operate a relay by
itself)
> which presents a dry contact closure to the SECU16 and that is what it
> wants. I realize that with up to 5 million meter revs per year the mean
time
> failure for the reed relay is two years. I am placing the $1.29 relay in
a
> socket.
> 
> 
> 
> -----Original Message-----
> From: joerut@epix.net [mailto:joerut@epix.net]
> Sent: Tuesday, January 16, 2001 11:14 AM
> To: ecs-list@netbloc.com
> Subject: Re: [ECS] Power Sentry & Secu 16
> 
> 
> Doug
> 
> Here is a copy of the data from the power sentry website. See below for
> suggestions on your situation.
> 
> 
> "Each Power Sentry sensor requires a small amount of power. The
controlled
> outputs of the ADC-1 can supply sufficient power to operate the Power
> Sentry. It is necessary to install a three conductor cable (power, ground
> and
> signal) between the ADC-1 computer/sensor interface and the Power Sentry.
> This cable can be as long as 200 feet.
> 
> The wires from the sensor have the following definitions:
> 
> Black - Ground (negative)
> 
> Yellow - Power (positive 5 -15 Volts DC) The Power Sentry must only be
> operated on voltages between 5 and 15 volts DC. Voltages greater than
these
> levels will permanently damage the sensor.
> 
> Red - Power (positive 5 -15 Volts DC)
> 
> Green - Sensor Signal Out (this signal will be either at ground or at the
> power supply voltage level, depending on whether the sensor is getting a
> reflection off the disk edge).
> 
> Connect the red and yellow wires and the positive leg of your power
source
> together. In some cases it may be necessary to install a 500 µf
> capacitor between power and ground to ensure that the sensor has
sufficient
> power
> at the instant that it transmits its' pulse"
> 
> 
> 
> You must connect the yellow and red wires together and connect them to a
> CLEAN  DC voltage (5-15 volts) The black is the ground wire and the green
> would go to the input of the PLC. I am not familar with the secu16 but if
> the
> input is not LATCHED then it could possibly MISS the pulse because it is
> so short. There are 2 ways around this either a oneshot circuit or a
large
> capacitor across the digital input. Let me know if you need more info.
> 
> Later
> Joe Rut
> 
> 
> 
> 
> > Rick,
> > Power Sentry
> > This sensor allows ECS to monitor your electrical power usage and
> estimate
> > your monthly bill. Inside every meter is a disk that rotates as
> electricity
> > is used. This sensor mounts on the outside of the meter glass and
> transmits
> > a pulse each time the disk completes a rotation (this represents 7.2
> > watt/hours on most meters). This output can be monitored via a
> > digital-input. It may also be connected directly to the INTERRUPT line
> of an
> > RS-232 cable, and monitored via a Serial-Byte Item.
> > Product name(s): Power Sentry
> > Distributor: Remote Measurement Systems (www.measure.com /
206-328-2255)
> > This is a cut and paste from ecs.htm. Mark also Details connection for
> the
> > PLC-Interface-2C) But thus far I have been unable to make it work with
> the
> > secu-16.
> >
> > -----Original Message-----
> > From: Rick Mortensen [mailto:rmorten@can-be-scanned.com]
> > Sent: Monday, January 15, 2001 8:51 PM
> > To: ecs-list@netbloc.com
> > Subject: Re: [ECS] Power Sentry & Secu 16
> >
> > Doug,
> > Could you be a little more specific regarding the Power Sentry?
> > ----- Original Message -----
> > From: Doug Storey <dastorey@swbell.net>
> > To: <ecs-list@netbloc.com>
> > Sent: Sunday, January 14, 2001 3:35 PM
> > Subject: [ECS] Power Sentry & Secu 16
> >
> > > I Finally got back to cutting the last 1/2 dozen circuits out of my
> time
> > > commander + and transferred over to the Applied Digital Secu 16's.
The
> > time
> > > commander will be for sell shortly. ( Shameless ad )  All is well
> except
> > for
> > > making the Power Sentry work.  Has anyone had experience with this
> combo.
> > > If so please share the connection scheme for the 4 leads on the Power
> > > Sentry.
> > > Tks
> > > Doug Storey
> > >
> >
> 
> 
 

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