MAC MAC155H, Instruction Manual

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©Copyright MAC Instruments 2005. All Rights Reserved. MAC155 Rev. 12
Pg 1
OVERVIEW
GENERAL
Always maintain AC power to the MAC155 Probe when the probe is
in place in the instrument port and the monitored equipment is
operating, (generating typical moisture).
There are no operator serviceable parts inside The MAC155 Probe
or Controller. Removal of the cover will increase the risk of electric
shock and contact of surfaces that can cause burns. Only trained
personnel familiar with this type of equipment and the hazards
involved should remove the covers.
The MAC155 is intended for use in continuously monitoring the water vapor
level in a stack or duct.
The MAC155 consists of two parts; a probe that mounts to a port on the stack
or duct that is being monitored, and a controller which is typically located in a
control room.
The MAC155 has multiple ranges which are user selectable using the display
and pushbuttons on the controller. It is necessary to do a calibration
sequence if the range is changed . The unit is shipped preset and calibrated to
the range indicated on the order. Refer to the blue factory configuration sheet
that was shipped with the unit for range information.
The MAC155 controller supplies AC and DC power to the probe. The probe
and controller communicate via an isolated RS485 serial port.
The % moisture level is displayed on the controller front panel and is
available as a 4–20ma or a 0–20mA analog signal at the rear of the controller.
4mA or 0mA represents 0% moisture by volume (MBV) and 20mA represents
100% MBV. The analog output can be forced to 0%, 25%, 50% 75% and 100%
of full scale using the pushbuttons on the front of the controller. This allows
testing of data logging equipment.