Optional step: Press Clear All [SK] to delete all stored depth information.

−− The operator may select a specific memory location to store the depth readings by pressing Mem Select [SK]. When the preferred location appears on the display, press Save [SK]. The display and memory location will populate with the current information.

−− Each memory location can be reviewed by pressing Mem Select [SK].

Press TRACE [2] or DEPTH [4] to return to Locate mode, or wait until receiver automatically returns to the Locate mode.

9. Locating Frequencies

A. Active Frequencies

Active frequencies are trace signals supplied by a 3MDynatelTransmitter 2500 Series (577 Hz, 1 kHz, 8 kHz, 33 kHz, 82 kHz or 200 kHz).

Select the same frequency that the transmitter is generating.

Press Menu/OK [5] (you may have to press Menu/OK [5] twice to toggle to the LOCATE MENU display).

Press Cable/Pipe[SK]

Press Freq [SK]

Press Active [SK Toggle] until the desired frequency is displayed: (“Active” 577, 1k, 8k, 33k, 82k or 200k)

Press Menu/OK [5] to return to Locate mode.

B. Power Frequencies

Power frequencies refer to 50 or 60 Hz signals, and their harmonics, that can be traced without the use of a transmitter.

60:Best for general locating of passive power.

60H (high harmonic): If the 60 choice appears to be responding slowly, or poorly, then 60H is the second choice for locating passive power.

60L (low harmonic): Third choice for passive power locating. May be used when 60 or 60H is weak or erratic. 60L may be the best choice when locating primary power cables.

120 Hz: Used for locating rectified AC power signals, often found on pipelines using impressed current cathodic protection.

Press Menu/OK [5] (you may have to press Menu/OK [5] twice to toggle to the LOCATE MENU display).

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3M 2550, 2573 manual Locating Frequencies, Active Frequencies, Power Frequencies