How to use Alarms in a GSD8 Digital DC Drive from AutomationDirect.com

The GSD8 Drives have very comprehensive and flexible alarming capabilities, which also means, at first glance, it’s a little overwhelming … so let’s break it down. Alarm 1 is dedicated to the Form-C relay on the drive terminal strip and uses parameters 50 through 67. Alarm 2 can be routed to any of the three option card slots on the drive and can do all the same things that Alarm 1 can do and is set up with Parameters 70 through 87. So, in this video, we’ll focus on Alarm 1 knowing we can do the exact same things using the Alarm 2 parameters. To create an alarm, you can monitor the acceleration/deceleration status, if the actual speed is outside the limits you set, if the target speed is outside those limits, if the target speed is zero, if the sensor pulses stop, if the master pulses stop (if you are in follower mode), if jog , inhibit or estop are enabled, if the drive’s output is maxed out, or if the drive is running. You can also monitor if any of the option card's alarms are active and if the maintenance the timer has expired. I have them separated because these use Parameters 50 through 52 while these use Parameters 65 through 67. You can alarm if any combination of these signals are active, but you can also qualify the alarms. Maybe you don’t want any alarms while the drive is inhibited or being jogged or if the target speed is zero or while the drive is ramping up to speed. You have complete control over those qualifications. And there are lots of other cool things you can do with alarms so let’s do a simple example, so we can see how all of this fits together. I’m using the same hardware that we used in the other videos where we have this drive, controlling this motor which is connected to this encoder which is wired back to the drive. We also have the same inhibit and jog switch wired into the drive and I added an indicator to show us the status of the relay output. Let’s suppose we want to alarm if the target speed the user enters exceeds our alarm limits, if the actual speed exceeds our alarm limits or if we lose encoder pulses. But, we only want to see alarms if we are not ramping up or down, if the inhibit switch is not active, the target speed is not zero, or if we are not jogging. Here are the parameters we are going to use. Let’s take them one at a time. First, let’s reset the drive to factory default so we are all starting in the same place. Go to Parameter 95, enter a 5, up arrow to confirm. And before we do alarm stuff, let’s go to parameter 12 and change the display to show us the actual speed so we can see when the drive is ramping up or down. Ok, we need to go to Parameter 50 to select what we want alarm one to go active on. The user manual has a chart that tells us what each alarm value is. We want to alarm on these, so we just sum those values and put that number in parameter 50. You might recognize that these values are just setting binary bits in a word. Parameters 51 and 52 choose under what conditions we DON’T want to alarm. We go back to the table, and we only want to alarm if these guys aren’t active. Sum that value and put that number here to enable those and here to invert them because we only want to alarm if they AREN’T active. If you want to alarm if something IS active, then don’t invert that one – which means you just don’t add his number to the sum for the invert parameter. Parameter 53 is the style and reset mode. Let’s start with just a constant alarm and have it automatically reset when the alarm condition goes away, which is the default, so we are good to go here. With Parameter 54 you can allow the alarm to be silenced or not, and if the reset comes from S2 or the enter key. The default is no silencing and reset on the enter key, so we’ll use that one for the first example. In Parameter 55 let’s enable the front panel LED for Alarm 1 so this guy will blink when we have an alarm. Parameters 56, 57 and 58 are for pulsed outputs, but we chose a constant output, so we can skip those. Parameter 59 is the lower limit alarm – let’s suppose we want to keep tight control over 1000 RPMs, so let’s make the lower limit 995, and Parameter 60 is the upper limit so let’s make that 1005 RPM. Anything outside of that range should give us an alarm if we aren’t ramping up to speed, at zero speed, inhibited or jogging. Terminal S2 defaults to Jog so we don’t need to change that. So, let’s go to Parameter 36 and change the jog speed to 1250 RPM which is outside of our alarm limit, so we can test that Jog doesn’t generate an alarm. Parameters 65, 66 and 67 are identical to 50, 51 and 52, except they add more things to monitor. The option card alarms and the maintenance timer alarm. None of which we need right now so we can ignore those. I’ll scroll down to Parameter zero and hit enter to exit parameter entry mode. Ok, let’s try it! If I start to scroll up to 1000 RPM, we don’t get an alarm because we are accelerating. But if we stop before getting there, sure enough Alarm 1 goes active. If I continue to 1000 RPM, then the alarm auto resets – exactly what we asked it to do back in Parameter 53. If we Jog to 1250 RPM, we don’t get an alarm because we told it not to alarm during Jog. Perfect. Let’s turn Jog off and drop the target to 990. Yep, the alarm comes back on because we are below the 995 RPM lower limit we set. If we go to 0 RPM we get no alarm - again because we told it not to in Parameters 51 and 52 – but if we go to 1 RPM we DO get an alarm. Of course, the motor doesn’t spin because it only works down to some minimum RPM. If we get the motor moving, then we get an alarm because we are not near the 1000 RPM we want. Let’s go back to Parameter 53 and change it to a manual reset. Exit parameter entry mode. We see we have an alarm active because we aren’t close to our running speed. If we move the speed back to our 1000 RPM, the alarm doesn’t automatically reset. And we have to hit the enter key to manually reset it. Exactly what we asked for. Finally, if we inhibit the drive, we don’t get an alarm – again, exactly what we told it to do. That should be enough to get you started with setting up alarms on the GSD8 family of drives. There’s lots of other options so now that you know how, go experiment with them and you will quickly see how comprehensive the alarming capability of these GSD8 drives is. Just remember that the GSD8-240-5C – the low-end drive - uses different parameter numbers and doesn’t support all of these options. You can see in the user manual there is a column that tells you which parameters apply to that guy and which parameters apply to all the other drives. Click here to see all the videos in this series. 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