User manual

µC
2
SE process chiller +030220416 - rel. 2.2 - 25.01.2013
2 logic times are considered:
- activation time
- deactivation time.
-
Activation/deactivation time
Activation time
The activation time is not a set parameter, but a value between 2 selected
parameters, i.e r08 and r09. As soon as the neutral zone is exited, the activation
time is practically r08, while at differential end r02 the activation time is r09. Within
the differential r02, the activation time varies in a linear mode between r08 and
r09. This means as you move away from the set, the intervention times are
reduced, in order to make the system response more dynamic.
Deactivation time
In the same way as the activation time, the deactivation time also varies depending
on a maximum, i.e. the value set by the parameter r10 in correspondence of the
set point temperature and a minimum, determined by parameter r11, in
correspondence with the differential end for the deactivation of compressors in this
mode, selected via parameter r12. Below this value the deactivation time will be
the same as the minimum set to the temperature value A04, beyond which all
compressors will be switched off, irrespective of times. On moving away from the
set point, a more dynamic process reaction is derived.
6.4.9 Outputs activation delay (par. c06)
On switch-on (intended as physical power supply of the controller), the activation
of all outputs is delayed by the time set to distribute the absorptions and protect
the compressor from repeated switch-ons in the event of frequent power-cuts. This
means that, after this delay period, the controller will start to manage the outputs
on the basis of the protections and the normal operations functions.
6.4.10 Compressors deactivation external temperature
(par.r25)
The compressors are deactivated if the external temperature drops below the value
of r25. The differential for re-activation is fixed at 1 degree. The resistances can be
activated according to the relative set-points.
6.5 Pumps management
6.5.1 Pump operation
H05 establishes the evaporator pump operating mode.
H05 = 0: pump disabled, (the flow switch alarm is ignored)
H05 = 1: always on (alarm managed)
H05 = 2: switched-on on regulator request (alarm managed)
H05 = 3: pump activated at regular ON and OFF intervals (with compressor in
OFF) according to parameters c17 and c18.
6.5.2 Minimum switch-on/off times
c17: below find the operating diagram of the pump in burst mode (active with H05
= 3). The burst operation is disabled in stand-by and during an alarm with pump
inhibited. On switch-on it is activated after time c17. c18 represents the minimum
time during which the pump remains active. See the following paragraph for
compressor-pump delays c07 and c08.
Par. Description
Def Min Max U.M.
r01 Set poin
t
12 r13 r14 °C/°F
r02 Differential 3 0.1 50 °C/°F
r06 Type of regulation/compressors use
0 = Proportional input
1 = Proportional input + neutral zone
2 = Proportional output
3 = Proportional output + neutral zone
4 = Timed output with neutral zone
0 0 4 -
r07 Neutral zone differential 2 0.1 50 °C/°F
r08 Output maximum activation time 120 0 999 s
r09 Output minimum activation time 100 0 999 s
r10 Output maximum deactivation time 120 0 999 s
r11 Output minimum deactivation time 100 0 999 s
r12 Compressors deactivation differential 2 0 50 °C/°F
r08
r09
B1
r02
Activation
time
r01
r07
r10
r11
B1
r12
Deactivation
time
r01
A04
A01
Par. Description
Def Min Max U.M.
c06 Outputs activation delay 0 0 999 s
Par. Description
Def Min Max U.M.
r25 Compressors deactivation external
temperature
-40 = function deactivated
-40 -40 80 °C/°F
ON
OFF
r25
B3
1
CMP
Key
CMP Compresso
r
B3 External probe
Par. Description
Def Min Max U.M.
c17 Pump minimum switch-off time 30 0 150 min
c18 Pump minimum switch-on time 3 0 15 min
t
c18
c07 c08
c17 c18
c17 c18
ON
OFF
ON
OFF
CMP
P
Key t: time
P pump CMP compresso
r
23