Important Cookie Information

This website uses absolutely necessary cookies. If you consent to the use of convenience cookies, please click “Yes, I agree.” By clicking on “Privacy Settings.” you can change this setting at any time and withdraw your given consent. Icon down see more You can find detailled information in our Privacy Policy Icon forward-right
Icon up see less

Bosch Building Technologies

    cancel
    Showing results for 
    Search instead for 
    Did you mean: 

    How to Troubleshoot a D125B Module

    Issue

    One of the zones at the panel is in constant trouble.
     
    Solution
     

    Need to have proper wiring connections.  Check the following:

    1. Using 12 Volt Smokes, Terminal 1 goes to Terminal 8 on the panel Switched AUX Power.

    2. Make sure D136 relay is installed for Relay C for non G-Series panels.

    3. For 24 Volt Smokes, Terminal 1 goes to a D130, and a UL 24 Volt PSU is needed on Terminal 8 on the Panel. Switched AUX Power goes to the D130 to reset the 24 Volt power.

    4. Measure the EOL across loop "A" Terminals 7 and 9 of the D125B card. Look for 1.8K Ohms for the D125B on a new install or when adding to an existing install. If replacing a D125 or D125A the EOL would be 1.5K Ohms.

    5. Measure the EOL across loop "B" Terminals 6 and 8 of the D125B card. Look for 1.8K Ohms on the D125B card on a new install or when adding to an existing install. If  replacing a D125 or D125A the EOL would be 1.5K Ohms.

    6. Measure the Voltage across  Loop "A" Terminal 3 and Terminal 4 on the D125B card. The meter should read 2.5VDC with everything connected. If the reading is 5VDC the loop is Open (not seeing the 1.8K EOL across the last Smoke. If the voltage reading is Less than 1VDC you have a Short on the loop. The short could be a smoke head latched in alarm, bad/dirty smoke head, wiring short, or reversed polarity to one of the smoke heads on the loop.

    7. Measure the Voltage across  Loop "B" Terminal 2 and Terminal 4 on the D125B card. The meter should read 2.5VDC with everything connected. If the reading is 5VDC the loop is Open (not seeing the 1.8K EOL across the last Smoke. If the voltage reading is Less than 1VDC you have a Short on the loop. The short could be a smoke head latched in alarm, bad/dirty smoke head, wiring short, or reversed polarity to one of the smoke heads on the loop.

    To verify the D125B is working correct you can wire the 1.8K Ohm EOL accross termainals 7 & 9 and another 1.8K Ohm EOL accross termainals 6 & 8.

    The Loop termainals 2 & 3 need to wire to the Positive Side of a 1K Ohm Zone. The EOL for the 1K Ohm zone is built in to the D125B.

    2018-06-12_09h19_22.png

    Part numbers D7212B, D9112B, D7212B1, D9112B1, D7212, D7412, D9112, D9124, D9412, D7412G, D9124G, D9412G, D7412GV2, D9124GV2, D9412GV2, D7412GV3, D9412GV3, D7412GV4, D9412GV4, B9512G, B8512G, D125B

    Version history
    Revision #:
    1 of 1
    Last update:
    ‎06-12-2018 03:19 PM
    Updated by:
     
    Labels (2)
    Contributors
    Icon--AD-black-48x48Icon--address-consumer-data-black-48x48Icon--appointment-black-48x48Icon--back-left-black-48x48Icon--calendar-black-48x48Icon--center-alignedIcon--Checkbox-checkIcon--clock-black-48x48Icon--close-black-48x48Icon--compare-black-48x48Icon--confirmation-black-48x48Icon--dealer-details-black-48x48Icon--delete-black-48x48Icon--delivery-black-48x48Icon--down-black-48x48Icon--download-black-48x48Ic-OverlayAlertIcon--externallink-black-48x48Icon-Filledforward-right_adjustedIcon--grid-view-black-48x48IC_gd_Check-Circle170821_Icons_Community170823_Bosch_Icons170823_Bosch_Icons170821_Icons_CommunityIC-logout170821_Icons_Community170825_Bosch_Icons170821_Icons_CommunityIC-shopping-cart2170821_Icons_CommunityIC-upIC_UserIcon--imageIcon--info-i-black-48x48Icon--left-alignedIcon--Less-minimize-black-48x48Icon-FilledIcon--List-Check-grennIcon--List-Check-blackIcon--List-Cross-blackIcon--list-view-mobile-black-48x48Icon--list-view-black-48x48Icon--More-Maximize-black-48x48Icon--my-product-black-48x48Icon--newsletter-black-48x48Icon--payment-black-48x48Icon--print-black-48x48Icon--promotion-black-48x48Icon--registration-black-48x48Icon--Reset-black-48x48Icon--right-alignedshare-circle1Icon--share-black-48x48Icon--shopping-bag-black-48x48Icon-shopping-cartIcon--start-play-black-48x48Icon--store-locator-black-48x48Ic-OverlayAlertIcon--summary-black-48x48tumblrIcon-FilledvineIc-OverlayAlertwhishlist