Accurate depth or lack their of

**Goldenboy** · July 28th, 2010, 09:45 PM

With all the advances in technology over the years why can't they make a locator that provides an accuate depth consistantly? It seems like it's 50/50 with the accuracy of the depth on modern locators. It is either right on or way off. It just seems like we've gone 5 years without seeing any real advances in the locating machines.

Why can't they add the ability to find the ELMK markers with your normal locator. I know RD had this years ago but shouldn't all locators have this feature. The utility companies spend the time and money to drop markers in every handhole and on most stubs but we have to hunt down an ELMK locator to find them.

**Dave72** · July 28th, 2010, 10:53 PM

Ive never gone back on routine to check my depths (we dont give em out as a rule anyhow), but when Im doin in-house locates for our own guys.. Ill try to get em a depth.
As long as peak and null both agree (important), then your depth reading should be bang on.
If peak and null dont agree, then something else is affecting the field and you cant get a depth on it.

Im not sure what a ELMK marker is, but Id think it would be poor biz practice to use some marker ball/etc that doesnt resonate at an industry standard freq (8, 33 etc)

**GWJ_CAS** · July 29th, 2010, 07:05 AM

Originally Posted by Dave72

Ive never gone back on routine to check my depths (we dont give em out as a rule anyhow), but when Im doin in-house locates for our own guys.. Ill try to get em a depth.
As long as peak and null both agree (important), then your depth reading should be bang on.
If peak and null dont agree, then something else is affecting the field and you cant get a depth on it.

Im not sure what a ELMK marker is, but Id think it would be poor biz practice to use some marker ball/etc that doesnt resonate at an industry standard freq (8, 33 etc)

It sounds like you guys are lacking knowledge about electronic markers and how they work. With electronic markers, the marker locator sends a signal to the passive marker that energizes it, this signal is reflected back to the locator. with a signal peak directly above the marker for precise location within inches. Electronic markers are immune to congestion and usually reliable as electronic markers are typically installed during construction when the facility is visible to the eye, making it a trusted method for positive identification of buried facilities.

Typical Marker Dimensions
Size 4.5 inch diameter (11.4 cm) Max.
Range 5 feet typical (1.5 meters)
Field Type Spherical
Package Material High-density polyethylene

Standardized Frequencies for Electronic Markers
Electrical Power Red 169.8 kHz
Water Blue 145.7 kHz
Sanitary Green 121.6 kHz
Telephone Orange 101.4 kHz
Natural Gas Yellow 83.0 kHz
Cable TV Black/Orange 77 kHz
Non-Potable/Gen1 Purple 66.35 kHz

**headcipher** · July 29th, 2010, 09:57 AM

There are 3 of the newer locators that can locate EMS markers. Vivax VlocMl, Metrotech i5000 metromark, and a new dynatel(forgot the model).

Hope that helps.

**yahoo** · July 29th, 2010, 08:22 PM

sorry to change the subject.........found out today that my vivax reciever does not have the radio feature....

**Mke** · July 30th, 2010, 10:11 AM

Hey Gregg, The marker balls are great if installed properly and they are limited to their "effective" range wich is, if memory serves me correctly 0'-5' they can be burried deeper but that shrinks the "zone" of detectability. I am looking into purchasing a locator to locate these, since the local city agency has fallen in love with them. They however are using them on a storm line that is 9' down. In the instruction to the balls, they state to strap them onto the utility, but to make sure they are no deeper then 5' or they have a "reduced" signature. Not too sure what all that means till I get a Locator in my hands and see for my self.

How is your experience with the Locator balls at depths past 5?

just curious.

mke

**headcipher** · July 30th, 2010, 12:52 PM

Past 5' it is rare to find a marker ball. The old mine sweeper style 3m units could because the gain went so high, but the newer ones are more limited by the FCC. Now if they use the big flat markers, or toilet seats as our company calls them, they can be located at a much greater depth. Of course the flat ones have to be installed in a more careful manner in order to work.

**GWJ_CAS** · July 30th, 2010, 02:00 PM

Originally Posted by Mke

Hey Gregg, The marker balls are great if installed properly and they are limited to their "effective" range wich is, if memory serves me correctly 0'-5' they can be burried deeper but that shrinks the "zone" of detectability. I am looking into purchasing a locator to locate these, since the local city agency has fallen in love with them. They however are using them on a storm line that is 9' down. In the instruction to the balls, they state to strap them onto the utility, but to make sure they are no deeper then 5' or they have a "reduced" signature. Not too sure what all that means till I get a Locator in my hands and see for my self.

How is your experience with the Locator balls at depths past 5?

just curious.

mke

Actually locating markers installed at depths greater than 5' is a hit & miss thing. sometimes you may get lucky and be directly over the marker and get a signal return, but at 9' depth the chances are slim to none. As Cipher points out, the "toilet Seat" markers are more effective for deeper installs, BUT, if they are not installed completely level, they will return bad location info.

**GWJ_CAS** · July 30th, 2010, 02:01 PM

Originally Posted by Mke

Hey Gregg, The marker balls are great if installed properly and they are limited to their "effective" range wich is, if memory serves me correctly 0'-5' they can be burried deeper but that shrinks the "zone" of detectability. I am looking into purchasing a locator to locate these, since the local city agency has fallen in love with them. They however are using them on a storm line that is 9' down. In the instruction to the balls, they state to strap them onto the utility, but to make sure they are no deeper then 5' or they have a "reduced" signature. Not too sure what all that means till I get a Locator in my hands and see for my self.

How is your experience with the Locator balls at depths past 5?

just curious.

mke

Actually locating markers installed at depths greater than 5' is a hit & miss thing. sometimes you may get lucky and be directly over the marker and get a signal return, but at 9' depth the chances are slim to none. As Cipher points out, the "toilet Seat" markers are more effective for deeper installs, BUT, if they are not installed completely level, they will return bad location info.