Contact J. R. Overseas company

If you have any questions or comments, please complete this form and we will get right back to you.

 

If you prefer to send us an email, email us at: sales@jroverseas.com 

Your Name
Your Name

44 Lexington Avenue
Gloucester, MA, 01930

978-526-0925

J. R. Overseas is a US company (Gloucester, Massachusetts) offering worldwide the finest in marine moisture and corrosion meters.  Our customers include safe-boating enthusiasts such as boat owners, boat manufacturers, marinas, boat yards, boat brokers and marine surveyors.

GRP33_KDSI_Blue2_2.jpg

Can I Recalibrate My GRP-33?

Instructions on how to re-calibrate the Electrophysics GRP33. 

Recalibration of GRP-33

Every now and then your GRP-33 may require recalibration.  Doing so is simple.

For a printable version of these instructions, click here.

Instructions:

The red pointer should to point to zero when the meter is turned off and held horizontally. If not, use a flat-bladed screwdriver to adjust the black screw.

TO CHECK THE ZERO-POINT Switch on the meter and hold it horizontally in mid-air, with your fingers well away from the sensing area on the rear. The meter should read 0%.

  • ADJUST THE ZERO IF NECESSARY AS FOLLOWS On the front panel there are two pale, almost white, plastic screw heads. Remove the left-hand screw, to expose a small hole in the meter body. Through the hole will be visible a white circle with a slot, just like a slotted screw head. Turn on the meter and hold it horizontally in mid-air. Take a small flatbladed screwdriver, and carefully insert the screwdriver blade through the hole to engage the white slot. Turn the screw very slowly until the needle points to the 0% mark. Re-insert the white plastic screw cap now, to avoid later confusion.

CALIBRATION CHECK (USING ACCESSORY CALIBRATION PLATE) There are two plates. Take the opaque copper-coated plate and place on a table top or other convenient non-metallic surface, with the copper side facing down. Place the second (clear plastic) plate on top of the first. Turn on the meter and place directly on top of the clear plastic plate and press gently. The meter should read 14%. If it does not, proceed as follows.

  • CALIBRATION ADJUSTMENT The meter remains on top of the clear plastic plate, on top of the opaque plate with copper side down. Remove the right-hand plastic screw to expose a small hole in the meter body. Through this hole is visible a white circle with a slot, just like the head of a screw. Take a small flat-bladed screwdriver and carefully insert the blade into the exposed hole to engage the slot. Turn the screw very slowly until the meter reads 14%. Re-insert the white plastic screw to keep foreign materials out of the meter. Both calibration plates should be kept flat, clean, and smooth. The copper coated plate should remain untarnished and corrosion free.

For a printable version of these instructions, click here.