1.What wiring connections are needed for the IVM6000?
The IVM6000 accepts a wide input voltage on the two “~” terminals. Consult the latest data sheet for up to date ranges, but at the timeof this post it was between 5V and 48V AC or DC.
AC voltage is preferred for long distance runs because it will have lower losses, and will also avoid accidental corrosion of wires due to electrolysis. Note that the power input to the IVM first goes through a “diode bridge” and therefore the polarity of the power wire connections does not matter. There is additional surge, discharge and lighting protection at the IVM as well.
The IVM will show and log errors on the local display, but two additional wires are required if you want the IVM to actually signal a contact closure at a control panel.
So 4 wires is the minimum suggested configuration, for future expansion it is suggested to run an 8 wire cable.
2. How do I interpret results when it’s Freezing cold?
We run several IVM600 Intelligent Valve monitors on a test system setup outside the back of our shop. It’s interesting to see how some common problems are picked up, and how the errors that are reported should actually be interpreted. In this example we’ll see how two consecutive errors (and assumptions about the weather) show the valve almost freezing up.
Notes about the oprating conditions:
- It’s January in Canada
- This valve monitor has a seat time set to 5 seconds.
- We’re pumping a 50% windshield washer antifreeze solution.
- The system is not insulated or heated.
This morning we checked an IVM6000 for errors, and the IVM reported:
5:36:12 Outlet Stuck #6 5:36:08 Inlet no Outlet
So what does this mean, How do you interpret these two errors in succession?
- At 5:36:02 the pump panel started pumping.
- The Inlet no Outlet occurred when the seat time was violated.
This means the valve’s internal disk only made it part of the way down, and didn’t seat on the outlet.
The pump then ran for another 4 seconds before the IVM reported Outlet Stuck.
- It (must have) reported Outlet Stuck because the previous dosing didn’t cause the cam to rotate the plunger.
Conclusion: This is a reasonable and plausible error since the operating conditions are very cold, it was 5:30 in the AM (likely the coldest point of the night) and internal icing could occur preventing the complete movement of the valve.
Corrective Action: If your system experiences freezing only very occasionally you may choose to ignore this type of error, and adjust the IVM sensitivity to medium or low. However, This is a sign that this part of the system is capable of freezing, and you may need to address that in some manner such as increasing the insulation around the valve.
Does the IVM6000 period timer reset itself?
If the valve was operating normally for say two years and then suddenly started to indicate a malfunction, would it take some time for the percents to vary, delaying the alarm.
Or are the percents calculated after each rotation forcing an alarm immediately?
Answer: Certain types of alarm conditions would cause it to alarm more or less “right away”. For example if it detects the valve is dosing the same zone/outlet over and over (several times in one day or in a row) or if it detects the valve is skipping one or more outlets every time it would alarm right away.
To capture an “uneven distribution” type of alarm condition, the percentages are calculated over a sliding period that can be set by the operator”. For a high cycling system you might want the monitor to calculate the average on a daily basis. For certain types of facilities where the wastewater flow rate will vary a lot throughout the week (ie. schools, restaurants) you might want to set the averaging period to 7 days, 30 days or more. The actual alarm condition is checked atregular intervals within the sliding period.
A period of 7 days means “the last 7 days” as opposed to “every 7 days”. So if the percentages go out of whack within the last seven days it will pick that up. In the example of a school system, this might cause an alarm to occur during spring break, as the flows to the septic system could abruptly change for that week, and the IVM might pick that up. A period of 30-60 days may be more appropriate.
The IVM will alarm whenever the variation of the data within that last period goes outside the user-configurable parameter “percent variation”. So for some systems a 15% variation might be acceptable but for others a 5% variation might be desired. There will be a balance between avoiding unnecessary alarms for minor “glitches” or variations that are not important and ensuring that if there is a serious problem the operator is notified.
We include some suggestions for how to best set these user configurable parameters in the user manual, or the default settings can be used to start off.