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IP Cams with dry relay contacts

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any IP cams that come with dry relay contacts activated by motion sensing ???

Marcel CCTV SPOKANE WA

509-720-7115

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Yeah, but he's looking for something that also has dry contact outputs... how many do, and how many are just TTL?

 

I did find this on the A&E sheet for the IQEye Alliance-Pro domes:

2.06 Event (Alarm) Handling Capability

A. The camera shall be capable of recording an event as pre and post event images to on-board SD Media Card. The camera shall also be able to transfer the event’s JPEG images to an FTP server via File Transfer Protocol (FTP). Events may be triggered using camera motion detection or from an external device input such as a relay.

B. When triggered from an external input or the camera’s motion detector, the camera shall be capable of sending JPEG images via e-mail and/or sequences of images to an FTP server or on-board compact flash if one is installed.

C. A relay output shall be available upon the activation of the camera’s motion detector or external relay input. The relay output may also be manually activated from the live view screen.

 

Doesn't specify dry contacts, but given the use of "relay" I would tend to assume it...

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Ok perhaps I just fell off the turnip truck but whats the difference in a Alarm output triggered by motion and a dry contact output triggered by motion?

With a ttl output you still need to use a low current relay to utilize the output. With a dry contact you can connect devices directly to it as long as the load current is not more than the contact current.

With a ttl output you need to use a relay like this http://www.altronix.com/index.php?pid=2&model_num=RBSNTTL

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The ttl in your scenario would still have current flowing through it to fire the relay.

This seems to be a gray area in our industry so I'm just trying to get some clarity.

 

Are we saying the dry contact will handle more current than the ttl?

If so how much?

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I looked at a Avigilon Camera and encoder. Here is what it says:

 

External I/O Terminals Alarm In, Alarm Out, RS-485

 

 

1

GND

Ground for RS-485 interface.

2

RS-485 RX/TX+

Half-duplex RS-485 interface for controlling external equipment.

3

RS-485 RX/TX-

4

I/O Common

Shared pin for Input and Output.

5

Input 4 (+)

The input uses a photocoupler and is electrically isolated from the internal circuitry. The input voltage should not exceed 12 V.

6

Input 3 (+)

Same as above.

 

7

Input 2 (+)

Same as above.

8

Input 1 (+)

Same as above.

9

Output 4

The output uses a photocoupler and is electrically isolated from the internal circuitry. The output terminal connections can be made with either polarity. The output can drive a maximum load of 50 V and 120 mA.

10

Output 3

Same as above.

11

Output 2

Same as above.

12

Output 1

Same as above.

 

So is that a dry contact or ttl?

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The ttl in your scenario would still have current flowing through it to fire the relay.

That is why TTL is not a dry contact output. it's a low current output.

This seems to be a gray area in our industry so I'm just trying to get some clarity.

 

Are we saying the dry contact will handle more current than the ttl?

If so how much?

TTL doesn't have dry contact. with a TTL, you still need to use a relay if you want to switch high current load. TTL is a voltage output with usually very small amount of current while relay is just like a switch

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Output 4

The output uses a photocoupler and is electrically isolated from the internal circuitry. The output terminal connections can be made with either polarity. The output can drive a maximum load of 50 V and 120 mA.

10

Output 3

Same as above.

11

Output 2

Same as above.

12

Output 1

Same as above.

 

So is that a dry contact or ttl?

its a TTL.

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TTL doesn't have dry contact. with a TTL, you still need to use a relay if you want to switch high current load. TTL is a voltage output with usually very small amount of current while relay is just like a switch

 

How much voltage and how much current?

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How much voltage and how much current?

 

Standard TTL circuits operate with a 5-volt power supply.

and output current between 5-15 mA (hope I remember correct did not touch them for years )

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Ok perhaps I just fell off the turnip truck but whats the difference in a Alarm output triggered by motion and a dry contact output triggered by motion?

With a ttl output you still need to use a low current relay to utilize the output. With a dry contact you can connect devices directly to it as long as the load current is not more than the contact current.

With a ttl output you need to use a relay like this http://www.altronix.com/index.php?pid=2&model_num=RBSNTTL

 

I just noticed that relay was a RBSNTTL

I assumed you were linking to a RBSN. Looks like I learned me something today. I had never heard of a RBSNTTL!

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