Humidity Control Operation; Gp Timer Set-Up; Trim Heater Control Via Ml Case Controller Range - Resource Data Management PR0109 User Manual

ML Switch User Guide

Humidity Control Operation

To utilise this feature a Humidity/Temperature Display is required (PR0445). Connect the Humidity/temperature display to the display port
on the ML Switch. The control algorithm will use the humidity reading from the display in calculating the percentage at which the trim
relays are to be pulsed.
When the measured rH is below the "Humidity Low" parameter the ML Switch will pulse the ML case controller trim relays to the duration
set by the "Trim Low" parameter. When the measured rH is above the "Humidity Low" parameter but below the "Humidity High"
parameter the ML Switch will pulse the ML case controller trim relays in proportion to the line drawn between the low and high levels.
When rH goes above the "Humidity High" level the ML Switch will pulse the ML case controller trim relays at the "Trim High" setting.
Setting the trim high parameter to 70% will result in 30 % energy savings as the controller trim relays will never pulse on for more than
70%. The trims are pulsed over a 5 minute period. Therefore if the ML Switch calculates the trim percentage as 50% then the trim relay
will be on for 2 and a half minutes and then off for 2 and a half minutes.

GP Timer Set-up

It is possible to set the ML Switch humidity control to operate at specific times. For this operation to occur set the parameter "Trim Mode"
to "Remote". A GP Timer channel must be set up to control the timer on/off periods of the ML Switch. For GP Timer set up please refer to
the Data Manager user guide found on the RDM website. The following settings should be followed in the GP setup.
Output Type
Output Mask
Output Channel
When the parameter "Trim Mode" is set to "Remote" and the Data Manager GP timer channel directed to the ML Switch is in the on
period the humidity control will operate as described above. During the Data Manager GP timer channel off period the relay will pulse to
the preset "Trim Off Level " parameter. For example if the trim off level is zero then the trims will be completely off. Thus allowing the user
to save energy when the store isn't trading and the trims are not required.
Note if you wish the ML controller trim relay to follow the Data Manager Trim Control feature and not the ML Switch settings then please
see the ML Controller user document.( Dependant on configuration

Trim Heater Control via ML Case Controller Range

Energy savings via the ML controller range can be achieved in a number of ways. One of which is pulsing the trim heater relay off for a
given period of time. One way to pulse the trim heater relay in the ML case controller range is by setting the parameter "Trim Level". This
sets a percentage level, of a 5-minute period, to pulse the trim heater relay off/on. Using this parameter pulses the trim relay irrespective
of the actual shop floor humidity. For greater energy savings the Data Manager energy feature trim control or the ML Switch trim control
feature can be used. These two options pulse the trim relay dependant on the actual shop floor humidity levels. Thus if the shop floor
humidity is relatively low the trim heaters can be pulsed off for longer durations. Please see the relevant user guides for further details.
RDM recommend that the trim heater pulse module is used in all instances (PR0723). This module is fitted in between the trim heater of
the case and the relay output of the ML Controller which is pulsing the heater. The trim heater module output provides a smoother power
distribution, compared to using the relay output direct, as it switches at the zero voltage crossover point. Switching the trim heater on and
off via a normal relay, without using the RDM trim heater pulse module, may damage the trim heater and reduce the operational life of
the heater. Therefore RDM recommend the use of this module in every trim heater control application.
Warning
Ensure that all power is
switched off before
installing or maintaining
this product
Humidity
High
Humidity
Low
– This should be set to "General".
– This should match the "Controller Name" e.g. "45a"
– Set to "13". This will allow the GP Timer to control the state of the timer.
parameter P-06 , P-07 and P-08 set to trims).
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