Setup/Tuning Loop - Thermo Scientific Merlin M75 Manual

Chapter 2

Setup/Tuning Loop

CAUTION
2 - 10 Merlin
The Setup/Tuning Loop, see illustration next page, is used to configure the
controller temperature display and various operating parameters. To enter the
loop you must be displaying the reservoir fluid temperature and then, while
pressing and holding
arrow keys to enter/bypass the loop. Once in the loop press
through it. Use the arrow keys to change any display.
The loop is used to determine how the chiller reacts when a fault occurs
— either shut down
configured to run.
It is also used to configure the temperature displays to indicate to a tenth of a
degree .
The loop is used to select which temperature sensor the high and low
temperature monitors uses
the optional external sensor.
properly connected to the rear of the chiller.
If the optional remote probe is enabled, the loop is used to set the remote
probe temperature deviation
to calculate the minimum fluid temperature supplied to your application. For
example, if the setpoint is 10°C and the deviation is set to 3°C, the coldest
fluid temperature supplied to your application is limited to 7°C.
The deviation can be set from 1°C to 53°C. The factory default setting is 50°C.
The loop can also be used to set the controller's PID parameters. The factory
preset values are in Chapter 4.
Thermo Fisher recommends that only a qualified technician change PID
parameters. Incorrect PID values will hamper chiller performance.
The heat PID is only applicable to chillers configured with a heater.
The loop is also used to adjust/verify serial communication parameters
. This section of the loop is applicable only to chillers configured for
serial communications capability.
Changes made in the Tuning/Setup Loop take affect when
the prompt. Pressing
, press . The display indicates
or continue to run
. is the internal sensor,
is available only if the external sensor is
limit. This limit is applied to the setpoint
at the prompt aborts all changes.
. Use the
to sequence
. The chiller is shipped
is

is pressed at
Thermo Scientific