Closed Captioning Below Video
The CP-50 EVSE Tester
Hi everybody today we’re going to go over the CP-50 test accessory. This is a piece of test equipment that you can use to verify the operations of a newly installed EVSE or charging station. It also has some additional functionality for some more advanced troubleshooting. So it’s a great tool for any installer or electrician to carry around in their tool bag, it’s hand-held, really compact, and it’s a great value.
So we’re going to go ahead and start with the basic verification of a newly installed EVSE of verification on any EVSE where you’ve got a vehicle you’re plugging in, it should be charging but it’s not charging.
So what we do with this here is we’re going to go ahead and plug it [SAE J1772 connector] into the CP-50 tester and then we’re going to activate a charge request. So the CP-50 in this
scenario simulates a vehicle being connected to the station and requesting a charge. So I’m going to go ahead and plug it in here, got it in there, and I’m going to switch from “charge not requested” to “charge requested” and when I do that what should happen is we should hear a click and we should see a green charging light on the EVSE come on. There’s also a red light on the side [of the CP-50] that will come on to indicate that power is being made available to the CP-50 from the EVSE.
So go ahead and do that. [Click] And we’ve got a click, we’ve got the green charging light on, and we have the red light on here [the CP-50] so in this case the EVSE has passed the test it’s properly responding to a vehicle’s request for charge. So I’m going to go ahead and switch that off and then we can next go into some more advanced troubleshooting with this volt meter.
And actually before I do that I’ll go ahead and we’re going to simulate a CCID fault this is a ground fault. So this fault is going to simulate current leaking to ground. One of the EVSE’s main functionality is to provide electrical safety for the user and it uses the CCID safety circuit to do that so when we trip this if the EVSE is functioning properly it should actually stop charging so the green light will turn off, you’ll hear the click again which is the contractor opening up and it’s removing power from the circuit, and then also a fault light will come on [the EVSE].
So go ahead and do that and we’ve got our fault light, the click, and the green charging light turned off and you’ll also notice that the red light on the CP-50 turned off so there is no power available on the tester.
Now we’re going to do some more advanced troubleshooting. So we’ve tested to make sure that the charging station properly responds to a vehicle’s request for charge; if you’re still having trouble charging your vehicle of if you just want to check out more information about the station we can use a digital volt meter to verify that when a charge is requested we have the proper voltage available and we can also test that we have the proximity latch circuit is functioning properly. There’s a circuit in the connector head that the vehicle’s going to be monitoring to make sure that it’s connected and able to request a charge.
So what we’ve done is after we did the CCID trip I went ahead and reset the station to clear that fault. You can reset the station just by cycling power just turning it off and then back on or you could let the fault clear automatically which it will do about after a minute so long as the fault condition has been removed.
So we’re going to go ahead and plug in our meter [to the CP-50]. So what we’re going to measure here is we’re going to measure each line to Ground and there’s ports on the CP-50 that you plug your meter into then we’re going to measure line to line for this test. So this is the voltage test so I’m going to go ahead and I’m going to turn my meter to volts AC and I’ll go ahead and plug into ground and I’ll go ahead and plug into Line One.
And what we should see is we should see 110 to 120 volts. In this case we’ve got 113 that’s Line One to Ground and we’ll go ahead and measure Line Two to Ground, should see approximately the same measurement, which we do, we’ve got 113 again, typically Line One to Ground and Line Two to Ground are going to be right around the same.
So then we’ll go ahead and measure each line to line and we should see somewhere between 208 to 240 volts depending on the transformer configuration at the site and here we’ve got 226, exactly what we would expect to see.
Now we’re going to go ahead and test the proximity circuit’s functionality. The vehicle monitors this circuit to make sure that the connector is fully inserted which needs to happen before the vehicle will request a charge. As you can see as you insert the connector the latch is going to lift up and once it’s fully inserted it’s going to seat down and now you can’t unplug it [without lifting the latch]. Okay good deal.
So we’ve got that and we’ll go ahead and turn our meter onto ohms to measure the resistance which is what we’re going to measure on this circuit. So I’ll plug in the Ground and the Proximity Test; what we should see here is about 140 ohms or resistance and then as I press the button here you’re going to see that resistance increase to around 400 ohms. And 406, and we’ll go ahead and push it down again, 142, this is within the spec. In the CP-50 User Manual it’s going to call out the specific range you’re looking to see for the resistance on the proximity circuit in each position. So this is functioning properly.
Next we can go ahead and do an additional test with and oscilloscope to verify that the station’s pilot communication signal is being generated properly and that we see a proper response when the vehicle requests a charge.
Alright so we’ve verified that the EVSE responds properly to a vehicle’s request for charge, we verified that we have the appropriate voltage available to the vehicle, and that our proximity latch is working properly and within spec. So if you’re still having issues charging a vehicle we can go ahead and use an oscilloscope to verify that the pilot signal being generated by the station is being generated correctly. This is a much more advanced troubleshooting that might be done by a mechanic in an automotive shop or more at an engineering level because not a lot of people have oscilloscopes but it is a capability of the product so we’re going to go ahead and go over it here.
So I’m plugged into the CP-50, we’ve got a charge being requested, we’re going to go ahead and actually turn that off for the test. So now we’re just connected to the vehicle but the charge is not requested. I’m going to go ahead and plug up the scope here. We’ve got the scope ports: there’s a Scope Ground and then a Scope Pilot, because we’re monitoring the Pilot Signal.
Alright so now you can see here we’ve got our pilot signal, it’s a square wave signal, you’ve got a positive portion of the signal which right now since we’re connected but charge is not requested should be around nine volts and you can see up here it is, it’s at 9.4, 9.6. And then you have the negative portion of the signal which should actually stay at negative 12 volts at all times and you can see here it’s at negative 12.
So now I’m going to go ahead and request a charge. We should see the positive portion of the Pilot Signal pull down to about six volts while the negative portion of the signal remains at 12 volts. And this negative portion of the signal remaining at 12 volts is something that a vehicle is monitoring for so you should see both of those things happen.
So we’ve got charge requested, we’re charging, we’ve got the positive portion now down at six volts and the negative portion of the signal is remaining at that 12 volt range. Based on these tests everything in the EVSE or the charging station is checking out, the signal looks good on the scope here and as I go ahead and remove the request for charge you’ll see it return up to nine volts.
So if you’re still having problems charging a vehicle it’s time to start looking at things on the vehicle the station is working as it should. If you have any additional questions or want to learn more about the CP-50 check out our website, give us a call and we’re happy to answer any questions or get you a quote so you can buy some.