TurboChef Technologies C3/CMulti - Manual (Page 42)

TurboChef Technologies, Inc. C Series
6-10
Defective Current Transformer on Computer Board
SMT Board (T0265) Background:
During the operation of the microwave system, the control board monitors current in the
microwave circuit by means of a current transformer mounted on the controller board.
The current transformer must see at least 6 amps in order for the microwave to energize.
If it fails to register 6 amps, the I/O board may be defective and the oven will prematurely
turn OFF the magnetron and display a "LOW MAG CURR/F3 MAG CURR" message.
Figure 6-2: SMT Board (T0265)
Checking the controller current transformer
Step 1: Place oven in TEST mode. Press BACK key until the oven screen displays " OVEN OFF" then
Press and hold the BACK and ENTER keys simultaneously and then key in PIN # 9-4-2-8 (access code)
then ENTER. This will allow you to enter into the test mode to manually energize the magnetron.
Step 2: Place a load inside the oven (about 275ml of water or an approximate amount inside a coffee cup).
Step 3: Clamp an ammeter on K4-1 wire (same wire going thru CT1 on controller board), and energize the
magnetron by pressing and holding the MGTRON key for about 10 seconds. If your meter measures
current (approximately 9 Amps+/- 2) and the W indicator at the bottom of the screen does not un-highlight
while energizing the magnetron, replace the computer board. If the measured current is between 6 and 7
Amps then double loop the wire thru CT1 twice, then perform a self test. If the self test fails then replace
board.
CT1