XLT Ovens AVI, Руководство по запчастям и обслуживанию

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HOOD THEORY OF OPERATION (W/FS) 17
HMC - The Hood Machine Control is a printed circuit board that has all the relays to control these
functions; oven activation SRC, MUA activation, VFD activation, monitors the air proving
switches, and lighting activation. The HMC receives a continuous 24 VDC power source provided
the CB I breaker is on. This component also has independent relays to control oven power for fire
suppression. If a signal from the fire system is received the oven(s) and lighting power is discon­
tinued and the VFD will run at full speed. For a World installation, sail switch monitoring is avail­
able just by answering some questions through factory mode programming. The HMC will also
program the PowerFlex 4M VFD each time the CB I breaker is turned on. ModBus communication
is used to change the frequency the VFD runs at depending on the number of ovens used. Error
messages will appear on the screen to help with troubleshooting. The screen will flash and beep
indicating a error has occurred, the alarm button can cancel this for 2 hours. If error has not been
fixed beeping will return. The HMC has filter cleaning reminders available.
LTl & LT2 - These are light bulbs at each end of the hood, and should illuminate when the HUI
light button is touched, touch it again and the light turns off
Ml - The Exhaust Fan Motor is a 3-phase, direct drive motor. In normal operation, it is powered
by the VFD and its RPM will vary as the frequency from the VFD varies. There are no user ser­
viceable parts in the motor, and the bearings are permanently lubricated.
M2 & M3 - The Cooling Fan Motor is a 24 VDC, direct drive motor. In normal operation, it is
powered through HMC. These fans are used to keep the control box for the hood cool. There are
no user serviceable parts in the motor, and the bearings are permanently lubricated.
PLUG 1, 2, & 3 - These are circular electrical plugs on one end of the Switch Relocation Cord
(SRC). The plugs connect to Receptacles 4, 5, & 6 on the back of the hood. The other end of the
SRC plugs into the oven wire harness, and eliminates the operator switch supplied in the oven.
Conversely, when the HUI on the hood is tu rn ed o ff , the corresponding oven is tu rn ed o ff as well.
PS -The Power Supply recti fi es line voltage to 24 VDC, and supplies power to the HMC, cooling
fa ns, and fi re suppression
Rl - Is a SPDT relay, which is an electrically operated switch. It uses an electromagnet to operate
a switching mechanism. Voltage is supplied from TS 1-9 to Ansul agent box. Once the fi re alarm
is activated voltage returns to TSI-10 over to HMC P8. That same voltage continues to Rl-1 acti­
vating the coil in the relay, causing the contacts in the relay to switch fr om NC to NO. This will
switch 24 VDC fr om terminal 6 to terminal 5 on the VFD causing the Ml to operate at 60 Hz.
R2 - Is a SPDT time delay relay, which is an electrically operated switch. It uses an electromag­
net to operate a switching mechanism. Voltage continues fr om Rl-6 to R 2 via the red wire activat­
ing the coil in the relay, causing the contacts in the relay to switch fr om NC to NO after one sec­
ond has expired. This action delays the application of the voltage on terminal (5) on the VFD.
REC 4, 5, & 6- These are circular electrical receptacles mounted on the back of the hood. The
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