Installation Of A Pormido 998 Mirror/Camera System

[taskswap]

Well, we are on a roll!!!! Got this back from Melissa at Pormido:

Hi Gary,

I just got the message from engineer right after I sent below email, as long as you can handle the connection well, 2 backup cameras are workable for the mirror:)

In addition she sent new firmware that allows zooming the rear camera. Not sure I need that, but why not?

I must say that I highly recommend Pormido for a company to work with on things like this. I've lost track of the number of messages Melissa and I've traded, but it must be around 70. She's always been quick to respond and both courteous and helpful.

And the timing is working out well. Our kids get here on Wednesday and we'll have company until January 5th. So no mirror/camera work will get done during that time. But I will get the 2nd camera on order and should easily have it by the 5th.

Also I have to order a relay. That's 'cause all of this works at 5v and the Bosch relays don't always pull in at that voltage. And I'm thinking about this HiLetgo 2pcs 5V One Channel Relay Module Relay Switch with OPTO Isolation. As it says it used an opto isolator so there's no chance of hurting the mirror from back EMF. But the downside is that I probably ought to put it in a small box.

Anyone have a better idea?

That relay should do fine although I'm not personally a fan of small screw terminals in automotive use. I know you've done battery cable work - do you have a small-gauge ferrule crimper? That would add some peace of mind to the connection...

I presume you know this but for the archives, here's the data sheet on that relay. This particular part is "sealed" which not all relays are, so that's good.

https://datasheetspdf.com/pdf-file/720556/Songle/SRD-05VDC-SL-C/1

One thing I do see is max input voltage is 110% of the rated value, so 5.5V. It's just a coil, it's not going to burn up if you give it a half volt more (at least not right away, lol). I'm sure that's not a problem for you, Gary, because this 5V setup is going to have a regulator. But if anybody is reading this and thinking of using this particular unit in the 12V part number for some other purpose, don't. A lot of "12V" relays aren't designed for automotive use and will fail pretty fast with dirty 14V+ from alternators.

Gary, that Pormido has some kind of power supply I'm sure. What's it rated for? I'm sure it's fine, this is just curiosity, but this relay does draw half a watt when energized...

[Gary Lewis]

That relay should do fine although I'm not personally a fan of small screw terminals in automotive use. I know you've done battery cable work - do you have a small-gauge ferrule crimper? That would add some peace of mind to the connection...

I presume you know this but for the archives, here's the data sheet on that relay. This particular part is "sealed" which not all relays are, so that's good.

https://datasheetspdf.com/pdf-file/720556/Songle/SRD-05VDC-SL-C/1

One thing I do see is max input voltage is 110% of the rated value, so 5.5V. It's just a coil, it's not going to burn up if you give it a half volt more (at least not right away, lol). I'm sure that's not a problem for you, Gary, because this 5V setup is going to have a regulator. But if anybody is reading this and thinking of using this particular unit in the 12V part number for some other purpose, don't. A lot of "12V" relays aren't designed for automotive use and will fail pretty fast with dirty 14V+ from alternators.

Gary, that Pormido has some kind of power supply I'm sure. What's it rated for? I'm sure it's fine, this is just curiosity, but this relay does draw half a watt when energized...

I do have a small crimper and can easily put ferrules on the leads. But I like solder connections better than screw terminals.

As for the power supply for the Pormido mirror & cameras, it is named Hardwire Kit for PR996,PR998,D50 and the output is rated at 5V & 3.0A. It is a pretty fancy unit as it has cut-off voltages of 11.3V, 11.8V or 12.1V. In other words, when your battery voltage gets to the preset it'll turn the mirror off. That's for when you set the mirror up for constant recording while parked, during which it'll be pulling ~650 ma. However, with the relay module pulling another 100 ma (90 for the relay and another 10 for the opto coupler?), I won't be leaving it in that mode very often.

Anyway, at 3 amps for the power supply we should be good.

[Gary Lewis]

I do have a small crimper and can easily put ferrules on the leads. But I like solder connections better than screw terminals.

As for the power supply for the Pormido mirror & cameras, it is named Hardwire Kit for PR996,PR998,D50 and the output is rated at 5V & 3.0A. It is a pretty fancy unit as it has cut-off voltages of 11.3V, 11.8V or 12.1V. In other words, when your battery voltage gets to the preset it'll turn the mirror off. That's for when you set the mirror up for constant recording while parked, during which it'll be pulling ~650 ma. However, with the relay module pulling another 100 ma (90 for the relay and another 10 for the opto coupler?), I won't be leaving it in that mode very often.

Anyway, at 3 amps for the power supply we should be good.

Did some more testing today by cutting the red and black wires in the cable to the rear camera. Here are some notes:

• If you disconnect the black wire while the system is powered up you have to power it down to get the rear camera's output back on the screen. But if you disconnect the red wire while the system is powered up the view comes back on as soon as you reconnect the red wire.

• The red wire is carrying 258 ma from the mirror to the camera, but the black wire is carrying 156 ma from the camera to the mirror. IOW, it is a ground.

• If you connect the black wire directly to ground the system boots up perfectly. But the black wire is then carrying 189 ma. However, with that connection the red wire is only carrying 232 ma. IOW, the black wire is up 33 ma and the red wire is down 26 ma.

And now for the bad news. I realized that while I'd tried grounding the black wire from the rear camera instead of connecting it to the mirror's black wire I hadn't tried taking the red wire from the rear camera to power. So I did - to 12v instead of 5v. And I blew the rear camera up. Dead. The smell, if not the smoke, came out.

But the mirror and the front camera still work. So hopefully the input to the mirror from the rear camera is good as well.

Anyway, I'm wondering if I should use a DP relay and switch both the ground and the power to the camera. I checked and with the system and camera off but always-hot power supplied to the mirror there's a few ma of current for several seconds, like a capacitor bleeding off, but it soon goes to zero.

Thoughts?

[taskswap]

Did some more testing today by cutting the red and black wires in the cable to the rear camera. Here are some notes:

• If you disconnect the black wire while the system is powered up you have to power it down to get the rear camera's output back on the screen. But if you disconnect the red wire while the system is powered up the view comes back on as soon as you reconnect the red wire.

• The red wire is carrying 258 ma from the mirror to the camera, but the black wire is carrying 156 ma from the camera to the mirror. IOW, it is a ground.

• If you connect the black wire directly to ground the system boots up perfectly. But the black wire is then carrying 189 ma. However, with that connection the red wire is only carrying 232 ma. IOW, the black wire is up 33 ma and the red wire is down 26 ma.

And now for the bad news. I realized that while I'd tried grounding the black wire from the rear camera instead of connecting it to the mirror's black wire I hadn't tried taking the red wire from the rear camera to power. So I did - to 12v instead of 5v. And I blew the rear camera up. Dead. The smell, if not the smoke, came out.

But the mirror and the front camera still work. So hopefully the input to the mirror from the rear camera is good as well.

Anyway, I'm wondering if I should use a DP relay and switch both the ground and the power to the camera. I checked and with the system and camera off but always-hot power supplied to the mirror there's a few ma of current for several seconds, like a capacitor bleeding off, but it soon goes to zero.

Thoughts?

They make relays that can establish one circuit before another (like a GND before power) but I don't think that's what you want. I may be misunderstanding but is there a reason you want to switch GND? That's usually left always connected so there's a reference for things like caps to drain out to, provide an EMF and static-discharge pathway, etc...

I suspect you're right that the video line is probably OK. Usually what fries is the front-end circuitry that buffers the power to the CCD (or the video would be noisy). To make those cameras so small they can't stuff big 60V rated electrolytics in there, so they're usually all surface mount caps and diodes. A lot of them these days are in 0403 and smaller packages and there just aren't enough molecules side by side to stand up to higher voltages. When a diode hits its breakdown voltage (which is low on small diodes) it basically becomes a short, and both it and any tiny resistors on the path just melt. Foosh.

It's a shame they didn't have a better clamp on that line, like a zener setup, but there's a reason these things are so cheap. But even that would only have given you a second or two to react before the same thing happened.

Anyway sorry your camera melted but maybe now you have the accidental excuse to look for the perfect shape/size to mount where you want it?

 

[Gary Lewis]

They make relays that can establish one circuit before another (like a GND before power) but I don't think that's what you want. I may be misunderstanding but is there a reason you want to switch GND? That's usually left always connected so there's a reference for things like caps to drain out to, provide an EMF and static-discharge pathway, etc...

I suspect you're right that the video line is probably OK. Usually what fries is the front-end circuitry that buffers the power to the CCD (or the video would be noisy). To make those cameras so small they can't stuff big 60V rated electrolytics in there, so they're usually all surface mount caps and diodes. A lot of them these days are in 0403 and smaller packages and there just aren't enough molecules side by side to stand up to higher voltages. When a diode hits its breakdown voltage (which is low on small diodes) it basically becomes a short, and both it and any tiny resistors on the path just melt. Foosh.

It's a shame they didn't have a better clamp on that line, like a zener setup, but there's a reason these things are so cheap. But even that would only have given you a second or two to react before the same thing happened.

Anyway sorry your camera melted but maybe now you have the accidental excuse to look for the perfect shape/size to mount where you want it?

I don't know that I need to switch ground. I measured the black wire back towards the mirror with power off and got 8 ohms. And measured it towards the camera, before blowing it up, and got 2 ohms. So I think I'll be fine taking the black wire from the camera to ground permanently.

But I'd actually suggested switch both power and ground to Pormido and it was that arrangement the engineer approved. So I've been wondering, aloud mostly. But, as said, it worked taken to ground, although it altered the currents. I'm guessing that the "drain" wire was being used as ground and by creating a better ground that current came over to the black wire.

And yes, it is a shame they didn't have a better clamp. But it is my fault.

However, I'm going back with the same camera. It will work and they are "only" $50 each.

[taskswap]

I don't know that I need to switch ground. I measured the black wire back towards the mirror with power off and got 8 ohms. And measured it towards the camera, before blowing it up, and got 2 ohms. So I think I'll be fine taking the black wire from the camera to ground permanently.

But I'd actually suggested switch both power and ground to Pormido and it was that arrangement the engineer approved. So I've been wondering, aloud mostly. But, as said, it worked taken to ground, although it altered the currents. I'm guessing that the "drain" wire was being used as ground and by creating a better ground that current came over to the black wire.

And yes, it is a shame they didn't have a better clamp. But it is my fault.

However, I'm going back with the same camera. It will work and they are "only" $50 each.

This all reminds me of the A-R-A add-on A/C system. The "digital thermostat" (ha!) module has this VERY explicit instruction that the unit must be grounded before being supplied power. I would never have known about it except for the thread here on that unit, where another member shared that wiring diagram that mentions it.

It's crazy to me because I have some (small but non-zero) amount of experience with general aviation, and there, literally everything is rated to minimum 40-60V to tolerate "load dumps" from the alternator without getting fried. But everything in our cars is so delicate! You can't "pull over" in a plane...

[Gary Lewis]

This all reminds me of the A-R-A add-on A/C system. The "digital thermostat" (ha!) module has this VERY explicit instruction that the unit must be grounded before being supplied power. I would never have known about it except for the thread here on that unit, where another member shared that wiring diagram that mentions it.

It's crazy to me because I have some (small but non-zero) amount of experience with general aviation, and there, literally everything is rated to minimum 40-60V to tolerate "load dumps" from the alternator without getting fried. But everything in our cars is so delicate! You can't "pull over" in a plane...

Yes, it is scary that these systems are so delicate. But it is easy to see why they are proprietary in their connections. They don’t want you to be mucking about with them - for good reason.

Anyway, I got the relays and project boxes on order tonight. Hopefully I’ll order the cameras tomorrow.

[Gary Lewis]

Yes, it is scary that these systems are so delicate. But it is easy to see why they are proprietary in their connections. They don’t want you to be mucking about with them - for good reason.

Anyway, I got the relays and project boxes on order tonight. Hopefully I’ll order the cameras tomorrow.

And as I've come to expect, Melissa came through and confirmed the part number of the cameras. And, said there were only two in stock at Amazon. They'll be here Thursday or Friday.

[Gary Lewis]

And as I've come to expect, Melissa came through and confirmed the part number of the cameras. And, said there were only two in stock at Amazon. They'll be here Thursday or Friday.

Houston, we have a problem. I just got this in:

Hi Gary,

Update comment from our engineer:

1) You cannot connect backup cameras to the system, otherwise, the front image will be 'GRAY' because currently the Front cam system is AHD, and the Back cam system TVI.

2) We recommend you place the current front camera to rear windshield(inside of the car), use it as rear camera, and use the backup camera as FRONT camera(waterproof), if the front camera cable is too short, we have 2 METERS extension cable, you can use THREE cables(6 meters).

Sorry for this delay message, actually we've been waiting for this engineer's confirmation but he's not in office(covid)...

So, after all this it is NOT going to work.

My response was that I cannot place either camera inside the cab. So it looks like I have but two options: package it all up and return it to Amazon, or put the front camera in a plastic box and put it on the nose of the truck like a wart.

I'm not a happy camper, so I'm going to bed to stew on it for the night. And since the grandtwins come tomorrow it may be a bit before I decide.

[taskswap]

Houston, we have a problem. I just got this in:

Hi Gary,

Update comment from our engineer:

1) You cannot connect backup cameras to the system, otherwise, the front image will be 'GRAY' because currently the Front cam system is AHD, and the Back cam system TVI.

2) We recommend you place the current front camera to rear windshield(inside of the car), use it as rear camera, and use the backup camera as FRONT camera(waterproof), if the front camera cable is too short, we have 2 METERS extension cable, you can use THREE cables(6 meters).

Sorry for this delay message, actually we've been waiting for this engineer's confirmation but he's not in office(covid)...

So, after all this it is NOT going to work.

My response was that I cannot place either camera inside the cab. So it looks like I have but two options: package it all up and return it to Amazon, or put the front camera in a plastic box and put it on the nose of the truck like a wart.

I'm not a happy camper, so I'm going to bed to stew on it for the night. And since the grandtwins come tomorrow it may be a bit before I decide.

Hmm that is a wrinkle.

Back on the encapsulation idea, what's the exact size of this front camera? Is it time to re-explore various options for protecting it while making it unobtrusive?