Emerson 1154, 00809-0100-4514 manual Sensing Module Checkout

Reference Manual

00809-0100-4514, Rev BA January 2008

Rosemount 1154

SENSING MODULE CHECKOUT

NOTE

Numbers in parentheses refer to item numbers in Figure 5-2 on page 5-5.

The sensing module (12) is not field-repairable and must be replaced if defective. If no defect such as a punctured isolating diaphragm or loss of fill fluid is observed, check the sensing module in the following manner:

1.Disengage the header assembly board (4) as described in step four of the electrical housing disassembly procedure on page 5-6.You need not remove the sensing module from the electrical housing for checkout.

2.Jump connections 1 and 2 on the header assembly board (see Figure 5-1 on page 5-2).

3.Using a low-voltage ohmmeter, check the resistance between the jumper wire and the sensing module housing. This resistance should be greater than 10 MΩ. Remove the jumper wire.

4.Jump connections 3 and 4 on the header assembly board and repeat step 3 (see Figure 5-1 on page 5-2).

NOTE

The above procedure does not completely test the sensing module. If circuit board replacement does not correct the abnormal condition and no other problems are obvious, replace the sensing module.

5-3